Tecumseh VLV Technician's Handbook

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TECUMSEH

VLV

ENGINES

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T E C H N I C I A N ' S H A N D B O O K

This manual covers VLV40 - 675.

Other illustrated Tecumseh 2-Cycle Engine, 4-Cycle Engine

and Transmission manuals; booklets; and wall charts are

available through Tecumseh.

For complete listing write or call

(VECTOR)

4-CYCLE

Page 2

TABLE OF CONTENTS

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Chapter 1 General Information .............................................................................. 1

Engine Identification ........................................................................................... 1

Engine Breakdown .............................................................................................. 2

Parts List ............................................................................................................. 3

Engine Care ........................................................................................................ 4

Fuel, Oils, Storage .............................................................................................. 4

Tune-Up Procedure ............................................................................................ 5

4-Cycle Engine Theory ....................................................................................... 6

Chapter 2

Air Cleaners ..................................................................................................... 7-8

Carburetion ......................................................................................................... 9

Identification ........................................................................................................ 9

Parts Breakdown................................................................................................. 9

Float Bowl Service ............................................................................................ 10

Float Bowl Reassembly .................................................................................... 11

Float Bowl Drain........................................................................................... 10-11

Rebuilding the carburetor body ......................................................................... 11

Welch Plug Removal ........................................................................................ 11

Cleaning Welch Plug and Installation ............................................................... 11

Throttle Shaft & Shutter .................................................................................... 12

Primer Bulb ....................................................................................................... 12

Chapter 3

Governors and Linkage ............................................................................... 13-14

Chapter 4

Starters ............................................................................................................. 15

Rewind Starter ............................................................................................. 15-16

12 Volts Starters .......................................................................................... 17-18

Chapter 5

Flywheels and Servicing ................................................................................... 19

Removal and Assembly ............................................................................... 19-20

Brake System Operation ................................................................................... 20

Wiring ................................................................................................................ 21

Battery .............................................................................................................. 21

Replace Brake Pad ........................................................................................... 21

Brake Mechanism Installation ........................................................................... 22

Control Switch & Replacement ......................................................................... 22

Chapter 6

Alternator .......................................................................................................... 23

Troubleshooting Electric Start Engines ............................................................. 23

Chapter 7

Ignition System ................................................................................................. 24

Ignition System Operation ................................................................................. 24

Spark Plug Service ........................................................................................... 23

Timing Adjustment ............................................................................................ 24

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Chapter 8

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Piston, Rings and Connecting Rod ................................................................... 25

Piston ................................................................................................................ 25

Rings ................................................................................................................. 25

Chapter 9

Cylinder and Cylinder Head Service ................................................................. 26

Reboring ........................................................................................................... 26

Cylinder Head ................................................................................................... 26

Chapter 10

Crankshaft, Camshaft and Lubrication.............................................................. 27

Crankshaft Timing Mark .................................................................................... 27

Camshaft Timing Mark ...................................................................................... 27

Compression Release....................................................................................... 27

Lubrication System Operation........................................................................... 28

Crankcase Breather Operation .................................................................... 28-29

Chapter 11

Valves, Lifters, Springs and Seats .................................................................... 30

Valve Removal .................................................................................................. 30

Valve Seats ....................................................................................................... 30

Valve Service .................................................................................................... 30

Valve Installation ............................................................................................... 31

Lifters ................................................................................................................ 31

Oversize Guides ............................................................................................... 31

Chapter 12

Removing the Mounting Flange ........................................................................ 32

Oil Seal Service ................................................................................................ 32

Mounting Flange Installation ............................................................................. 32

Chapter 13

Troubleshooting ........................................................................................... 33-39

Chapter 14

Engine Specifications ....................................................................................... 40

Torque Specifications ....................................................................................... 41

Chapter 15

Training Aids and Tools .................................................................................... 42

Chapter 16

Sears Craftsman Cross Reference ................................................................... 45

Tecumseh Products Company

C 1996

Page 4

Chapter 1

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GENERAL INFORMATION

ENGINE IDENTIFICATION

Tecumseh engine model, specification and serial numbers are stamped or decaled on the blower housing. The decal also contains any emission compliance information.

The letters which precede the model numbers indicate the basic type of engine:

VLV - Vector Lightweight Vertical

The numbers which follow engine type letters indicate the basic engine horsepower:

40 - 4.0 Horsepower

50 - 5.0 Horsepower

Following the engine size numbers are the engine specifications numbers.

The specification number is used when identifying engine parts example 502012A.

The serial number is the production date code.

7040 - serial number (example)

7 - Year in decade of manufacture (1997)

40 - The last 3 digits of date code represent the

calendar (the 40th day of 1997)

D - represents the shift and line on which the

engine was built at the factory.

VLV60-502012A

VLV60-502012A (D)

6215C

Emissionized engines that meet the California Air Resource Board (C.A.R.B.) or the Environmental Protection Agency (E.P.A.) standards will include additional required engine information on the engine decal.

NOTE: To maintain best possible emission performance, use only Genuine Tecumseh Parts.

SHORT BLOCKS. New short blocks are identified by a tag marked SBH (Short Block Horizontal) or SBV (Short Block Vertical). These tags are used to properly identify the correct parts if service is required. They are attached to either the sump bolts or valve box cover.

THIS ENGINE MEETS 1995-1998

CALIF. EMISSION REGULATIONS FOR

ULGE ENGINES AS APPLICABLE

FUEL: REGULAR UNLEADED OIL: USE SAE 30

VLV60-502012A (D) RTP358UIG2RA

207cc

6215C

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NOTE: On newer VLV models the breather

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tube will be a straight hose.

OPTIONAL PRE-FILTER

MODEL and SERIAL

NUMBERS HERE

PARTS IDENTIFICATION This is a parts breakdown of a typical VLV engine. Use this parts breakdown to identify parts. When ordering parts always refer to the engine model and specification number stamped on the engine blower housing.

Carburetor and starter breakdowns are found in the chapters referring to their repair.

SBV-XXX SER-XXX

NOTE: If the short block has been replaced, an identification tag for service parts is located on the valve box cover.

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Ref.

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No. Part Name 1 Cylinder Assy. 2 Pin, Dowel 3 Element, Breather 4 Cover, Breather 5 Gasket, Breather cover 6 Screw, Thread forming, 10-24 x 1/2 7 Body, Breather valve 8 Valve, Breather check 9 Breather, Tube 10 Washer, Flat 11 Rod, Governor 12 Lever, Governor 13 Clamp, Governor lever 14 Screw, 8-32 x 5/16 15 Spring, Governor extension 16 Seal, Oil 17 Baffle, Blower housing (Incl. No. 195) 18 Screw, 1/4-20 x 5/8 19 Crankshaft Assy. 20 Piston & Pin Assy. 21 Ring Set, Piston 22 Ring, Piston pin retaining 23 Rod Assy., Connecting 24 Bolt, Connecting rod 25 Lifter, Valve 26 Camshaft Assy. 27 Pump Assy., Oil 28 Gasket, Mounting flange 29 Flange, Mounting 30 Plug, Oil drain 31 Seal, Oil 32 Washer, Flat 33 Gear Assy., Governor 34 Spool, Governor 35 Ring, Retaining 36 Gear, Idler 37 Screw, 1/4-20 x 1-9/16 38 Key, Flywheel 39 Flywheel 40 Fan, Flywheel 41 Washer, Belleville 42 Nut, Flywheel 43 Solid State Assy. 44 Cover, Spark plug 45 Screw, 10-24 x 1 46 Wire Assy., Ground 47 Gasket, Cylinder head 48 Head, Cylinder 49 Valve, Exhaust 50 Valve, Intake 51 Screw, 5/16-18 x 1-1/2 52 Spark Plug (Champion RJ-19LM or equivalent) 53 Spring, Valve

Ref. No. Part Name

54 Cap, Valve spring 55 Gasket, Valve cover 56 Cover, Valve spring box 57 Screw, 10-24 x 1/2 58 Stud, Carburetor mounting 59 Link, Governor 60 Spacer, Carburetor mounting gasket 61 Lever Assy., Brake 62 Lever, Brake control 63 Link, Brake control lever 64 Spring, Brake 65 Ring, Retaining 66 Terminal 67 Spring, Brake control lever 68 Bushing, Brake control leer & brake lever 69 Spring, Compression 70 Spring, Compression 71 Screw, 5-40 x 7/16 72 Screw, 6-32 x 21/32 73 Gasket, Carburetor to air cleaner 74 Body, Air cleaner (Incl. Nos. 239, 299 & 350) 75 Screw, 10-32 x 2-3/32 76 Filter, Air cleaner (Paper) 77 Cover, Air cleaner 78 Nut, Lock, 1/4-20 79 Screw, 1/4-20 x 11/16 80 Plate, Control Assy., cover 81 Screw, 8-32 x 1/2 82 Housing, Blower 83 Screw, 1/4-20 x 1/2 84 Ring, Starter 85 Muffler 86 Plate, Muffler locking 87 Screw, 5/16-18 x 2-11/32 88 Cup, Starter 89 Screw, 8-32 x 21/64 90 Line, Fuel 91 Clamp, Fuel line 92 Clip, "U" Type Nut, 10-32 93 Tank Assy., Fuel 94 Cap, Fuel 95 Tube, Oil fill 96 "O" Ring 97 Clip, Fill tube 98 Dipstick, Oil 99 Plug, Starter 100 Screw, 10-32 x 35/64 101 Primer 102 Decal, Instruction 103 Decal, Primer 104 Carburetor 105 Starter, Rewind

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ENGINE CARE

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FUELS. Tecumseh Products Company strongly recommends the use of fresh, clean, UNLEADED regular gasoline in all Tecumseh engines. Unleaded gasoline burns cleaner, extends engine life and promotes good starting by reducing the build-up of combustion chamber deposits. Gasoline, gasohol containing no more than 10% ethanol, 15% M.T.B.E. or ETBE, leaded fuel can be used if regular unleaded is not available.

STORAGE

NEVER STORE ENGINE WITH FUEL IN TANK INDOORS OR IN ENCLOSED, POORLY VENTILATED ENCLOSURES, WHERE FUEL FUMES MAY REACH AN OPEN FLAME, SPARK OR PILOT LIGHT AS ON A FURNACE, WATER HEATER, CLOTHES DRYER OR OTHER GAS APPLIANCE.

If engine is to be unused for 30 days or more, prepare as follows:

Never use gasoline containing METHANOL, gasohol containing more than 10% ethanol, gasoline additives, or white gas because engine/fuel system damage could result. If engine is to be unused for 30 days or more see “STORAGE” instructions.

ENGINE OIL:

USE A CLEAN, HIGH QUALITY DETERGENT OIL. Be sure original container is marked: A.P.I. service “SF” or “SG”.

DO NOT USE SAE 10W40 OIL.

FOR SUMMER (ABOVE 32oF) USE SAE 30 OIL.

Using multigrade oil may increase oil consumption.

FOR WINTER (BELOW 32oF) USE SAE 5W30 OIL.

(SAE 10W is an acceptable substitute.)

(BELOW 0oF ONLY): SAE 0W30 is an acceptable substitute.

OIL CHANGE INTERVALS. Change oil after first two (2) hours of operation and every 25 hours thereafter, or more often if operated under dusty or dirty conditions.

OIL CHECK. Check oil every 5 hours or each time the equipment is used. Position equipment so the engine is level when checking the oil.

DRAIN INTO APPROVED CONTAINER

OUTDOORS, AWAY FROM OPEN FLAME.

1. DRAIN FUEL SYSTEM: Remove all gasoline from carburetor and fuel tank to prevent gum deposits from forming on these parts and causing possible malfunction of engine. NOTE: VLV engines are equipped with a bowl drain screw. See Chapter 2 for removal procedure.

A. Run engine until fuel tank is empty and engine

stops due to lack of fuel.

B. Disconnect fuel line at carburetor or fuel tank.

Be very careful not to damage fuel line, fittings or fuel tank.

Drain any remaining fuel from system. Properly reconnect the fuel line.

NOTE: If gasohol has been used, complete preceding instructions “A” and “B” and then put a small amount of unleaded (or leaded regular) gasoline into fuel tank and repeat preceding instructions “A” and “B”.

NOTE: Fuel stabilizer (such as STA-BIL) is an acceptable alternative in minimizing the formation of fuel gum deposits during storage. Add stabilizer to gasoline in fuel tank or storage container. Always follow mix ratio found on stabilizer container. Run engine at least 10 minutes after adding stabilizer to allow it to reach carburetor.

2. If oil has not been changed recently, this may be a

3. Remove spark plug and put 1/2 oz. (15 ml) of clean

4. Clean engine by removing any clippings, dirt, or

good time to do it. See “CHANGE OIL” instructions in “MAINTENANCE” section of the Owner’s Manual.

engine oil into spark plug hole. Crank engine over, slowly, several times.

AVOID SPRAY FROM SPARK PLUG HOLE WHEN CRANKING ENGINE OVER SLOWLY.

Reinstall spark plug.

chaff from exterior of engine.

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TUNE-UP PROCEDURE

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CAUTION: Remove spark plug wire before doing any service work on engine.

1. Service or replace air cleaner as necessary. (See Chapter 2 Air Cleaners)

2. Inspect level and condition of oil, change or add oil as required.

3. Remove blower housing, clean all dirt, grass or debris from intake screen, head and cylinder cooling fins and carburetor governor levers and linkage.

4. Make sure fuel tank, fuel filters and fuel lines are clean. Replace any worn or damaged governor springs or linkage. Make proper governor adjustments where required. (See Chapter 3)

NOTE: If the engine is equipped with a Tecumseh fuel tank, an integral filter is molded inside.

STANDARD

PLUG

9. Run engine and allow it to warm up for 5 minutes. After the engine is warm, set the engine governed RPM to specifications. This information is located only on Micro Fiche Card 30 or the Plus One and Parts Smart computer look-up systems.

5. Replace the spark plug with the proper spark plug. Consult the parts breakdown for the spark plug to be used in the engine being serviced. The spark plug air gap is .030'’. Install spark plug in engine and tighten to 15 foot pounds torque. If a torque wrench isn’t available, screw spark plug in as far as possible, by hand, and use a spark plug wrench to turn spark plug 1/8 to 1/4 turn further when reusing spark plug, or 1/2 turn further if using a new spark plug.

6. Make sure all ignition wires are free of abrasions, breaks and are properly routed so they will not rub on flywheel.

7. Properly reinstall the blower housing, gas tank, and fuel lines, then properly check for spark as stated in the ignition section of this manual.

8. Make sure all cables are adjusted for proper operation.

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4-CYCLE ENGINE THEORY

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Tecumseh four-cycle engines require four strokes or cycles to complete one power cycle.

1. INTAKE. Intake valve is open, exhaust valve is closed. Piston is traveling downward creating a suction action, drawing the fuel-air mixture from the carburetor into the cylinder area above the piston.

1. INTAKE

2. COMPRESSION. As the piston reaches Bottom Dead

Center, the INTAKE valve closes. The piston then rises, compressing the fuel and air mixture trapped in the combustion chamber, because both valves are closed.

3. POWER. Both valves remain closed. As the piston reaches the Before Top Dead Center (BTDC) ignition point, the spark plug fires, igniting the fuel-air mixture. In the time it takes to ignite all the available fuel, the piston has moved to TDC (Top Dead Center), ready to take the full combustive force of the fuel for maximum power and piston downward travel. The expanding gases force the piston down.

3. POWER

4. EXHAUST. Exhaust valve opens. As the piston starts

to the top of the cylinder, the exhaust gases are forced out.

After the piston reaches Top Dead Center (TDC), the four cycle process will begin again as the piston moves downward and the intake valve opens.

2. COMPRESSION

NOTE: Some emission compliance engines may use a

RCR (Ramp Compression Relief) system. This system opens the intake valve during the compression stroke allowing a small amount of the intake charge back down the intake pipe. This eliminates unburned fuel going out the exhaust during normal compression relief cycle typically used on the exhaust valve.

4. EXHAUST

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Chapter 2

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AIR CLEANERS

CAUTION: Before removing air cleaner, make sure ALL

excess dirt is removed from around it.

NOTE: If the engine is equipped with an optional poly pre-filter always remove it first, to prevent dirt falling into the filter body.

Air cleaners must be serviced frequently, to prevent dust and dirt from entering the engine. Dust mixed with the engine oil forms an extremely abrasive compound which quickly wears out an engine.

A clogged air cleaner will affect engine performance.

Replacing a restricted (clogged) air filter should restore engine performance.

AIR CLEANER SERVICE. The engine utilizes a treated paper element with a foam rubber-like sealing edge. The seal must fit properly to prevent dirt ingestion.

Replace air filter once a year or more often in extremely dusty or dirty conditions.

DO NOT ATTEMPT TO CLEAN OR OIL THE PAPER FILTER.

Be sure to clean base and cover thoroughly before installing new paper filter.

POLYURETHANE-TYPE PRE-FILTERS. These serviceable air filters utilize a polyurethane element which will clog up with use. The element should be cleaned and serviced in the following manner.

Wash element in a detergent and water solution and squeeze (don’t twist) until all dirt is removed. Rinse thoroughly.

Wrap in a clean cloth and squeeze (don’t twist) until completely dry.

Re-oil element by applying a generous quantity of oil to all sides. Squeeze vigorously to distribute oil and to remove excess oil.

Clean air cleaner housing and cover. Dry thoroughly.

Reinstall pre-cleaner in air filter body.

SOME VECTORS ARE EQUIPPED WITH BOLT ACCESS HOLE & A PLUG. REPLACE IF REMOVED.

POLY PRE-FILTER

NEVER RUN THE ENGINE WITHOUT THE COMPLETE AIR CLEANER INSTALLED ON THE ENGINE.

NOTE: Serious damage to the engine may result from using any other but the specified part number filter. Use factory recommended parts only.

Some models use a dual stage air cleaner. This air cleaner uses a polyurethane-type foam pre-filter along with the paper element.

PLUG

BODY

PAPER FILTER

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TO SERVICE AIR CLEANER

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1. Loosen cover screw (A).

2. Swing cover down and remove from hinge (B).

3. Pull foam pre-filter out of air cleaner body (if equipped with pre-filter).

4. Pull air filter out of air cleaner body.

5. Clean air cleaner cover and body.

6. Install a new paper filter (part no. 36046) (C).

7. Clean and install pre-filter (if so equipped).

8. Reinstall cover to air cleaner body.

Be sure hinge is assembled properly.

9. Swing cover up and tighten cover screw. (Do not over tighten).

PRE-FILTER

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CARBURETION

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Proper Carburetion Function is dependent on clean fresh fuel and a well maintained air cleaner system. Most causes of carburetion problems are directly related to stale fuel and dirt ingestion. Inspection of the carburetor for dirt wear and fuel deposits should always be done before servicing the carburetor.

Carburetor Identification:

Tecumseh carburetors are identified by a manufacturing number and date code stamped on the carburetor as shown. When servicing carburetors, use the engine model number or the manufacturing number on the carburetor to find repair parts in the Master Parts Manual.

The engine has used both a split system and married system carburetor. Below are the parts breakdowns for the two carburetor's.

SPLIT

37 38

MANUFACTURING NUMBER AND DATE CODE

TORX E-5 STUD

NOTE: LATER MODEL VECTOR CARBURETOR BODIES ARE HELD ON WITH TORX E-5 STUDS. YOU WILL NEED THIS SOCKET FOR REMOVAL. TECUMSEH PART NO. 670339.

Ref. No. Part Name

1 Throttle Shaft & Lever Assy. 5 Dust Seal (Throttle) 6 Throttle Shutter 7 Throttle Shutter Screw 25 Float Bowl 25A Idle Restrictor 26 Float 27 Shaft, Float 29 Gasket, Float Bowl to Body

25A

30 Inlet Needle, Seat & Seat Retainer (Incl. 31)

31 Seat Retainer

32 Bowl Drain Assy. 36 Tube, Main Nozzle 37 O Ring, Main Nozzle Tube 38 Spring, Main Nozzle Tube 39 Float Bowl Retainer 47 Welch Plug, Idle Mixture Well

MARRIED

NOTE: The seat retainer may not be present on some engines. If you receive a retainer as a service part, install it.

25A

25 37A

38A

Ref. No. Part Name

1 Throttle Shaft & Lever Assy. 5 Dust Seal 6 Throttle Shutter 7 Throttle Shutter Screw 25 Float Bowl 25A Idle Restrictor 26 Float 27 Float Shaft 29 Gasket, Float Bowl to Body 30 Inlet Needle, Seat & Seat Retainer (Incl. 31)

31 Seat Retainer

32 Bowl Drain Screw 33 Bowl Drain Washer 36 Tube, Main Nozzle 37 O Ring, Main Nozzle Tube 37A O Ring 38 Spring, Main Nozzle Tube 38A Spring 39 Float Bowl Retainer 40 Main Fuel Jet 47 Welch Plug, Idle Mixture Well

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The carburetor is a float feed, nonadjustable type,

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with a 1 piece extruded aluminum body. The float bowl, float, nozzle, and venturi are nonmetallic, minimizing the corrosion and varnishing problems. Common service areas of the carburetor are contained in the fuel bowl. These areas are the float, needle, seat and main nozzle. All of these parts can be serviced without removing the carburetor body from the engine.

DRAIN INTO APPROVED CONTAINER

OUTDOORS, AWAY FROM OPEN FLAME.

FLOAT BOWL SERVICE. Disconnect and plug the fuel

line. Remove the bowl drain screw. Remove the float bowl by snapping the bale spring towards the throttle end of the carburetor.

IF A SCREW DRIVER OR SIMILAR TOOL IS USED TO AID IN THE BAIL REMOVAL, CARE MUST BE TAKEN NOT TO PERMANENTLY BEND THE RETAINER.

AIR BLEED HOLES

SPLIT SYSTEM MAIN JET JET AND NOZZLE ASSY.

"O" RING

MARRIED SYSTEM MAIN JET

The float is held in the float bowl by the float pin which is pressed into tabs on top of the float support towers. NOTE: To prevent damage to the float bowl, pull straight up with a needle nose pliers in the pocket closest to the main fuel well. Carefully lift the float out of the float bowl and inspect for damage or deposits. Clean the idle passageway with compressed air, or with tag wire.

IDLE PASSAGE

After the bowl gasket is removed, the parts contained in the bowl can be inspected and serviced. Pull out the main nozzle and spring. Inspect the main nozzle for deposits, be sure to check the cross holes on the body of the nozzle and the main orifice in the bottom of the nozzle. Use compressed air or monofilament fishing line to remove any deposits in the main jet or cross holes. Remove the drain screw to access the spring, jet and "O" ring. The main jet should be inspected and cleaned if deposits exist.

MAIN NOZZLE

FLOAT

HINGE PIN

NOTE: The inlet needle is attached to the float and should also be inspected for damage or deposits.

The inlet seat can be removed with a small wire hook or a #2 crochet hook. Inspect the float bowl and main nozzle area for sediment and deposits. Use a carburetor cleaner to loosen and remove deposits and sediment.

INLET NEEDLE SEATS AT THIS POINT

INSERT GROOVED FACE FIRST

INLET SEAT

RETAINING CLIP

IDLE PASSAGE

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5/32" FLAT PUNCH

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SEAT

Place a new gasket on top of the float bowl with the notch on the gasket aligned with the bump on the bowl edge (the gasket will only fit onto the float bowl one way.) Hold the float bowl to the carburetor body and snap the retainer into position. Reinstall the bowl drain screw, do not over tighten, reattach the fuel line.

PRESS IN UNTIL SEAT RESTS ON BODY SHOULDER

INLET NEEDLE SEATS AT THIS POINT

RETAINING CLIP

INSERT GROOVED FACE FIRST

Install a new inlet seat into the float bowl. The grooved side of the inlet seat goes into the float bowl first. Place a drop of oil on the seat and press it in with a flat punch until it seats. Do not scratch the inlet bore.

NOTE: Some models are equipped with a fuel inlet seat retaining ring. If your replacement seat set comes with a retaining clip install it on top of the seat.

Slide the inlet needle into the tabs on the float and put the float pin into the hinge on the float. Carefully set the float into position in the float bowl.

Be sure the needle drops into the fuel inlet. Snap the float shaft into the tabs in the float bowl. It is not necessary to adjust the float height even if the float has been replaced.

Drop the main nozzle spring into the main nozzle well in the float bowl. Put a small amount of oil on the main nozzle “O” ring and push the nozzle into the main nozzle well, “O” ring end first.

NOTE: Bowl service is all that is normally required for routine carburetor maintenance.

Rebuilding the carburetor body:

Before disassembling the carburetor body, check the throttle shaft and body for excessive wear. If there is excessive wear to the throttle body, it should be replaced.

To rebuild the carburetor body it is necessary to remove the carburetor from the engine.

1. Remove the speed control plate.

2. Remove the air cleaner body from the carburetor.

3. Disconnect and plug the fuel line.

4. Remove the carburetor mounting studs.

5. Remove the governor link.

6. Drain the carburetor float bowl.

7. Disassemble the float bowl (see bowl service).

To properly clean the carburetor body, the welch plugs should be removed to expose drilled passages. To remove welch plug, sharpen a small chisel to a sharp wedge point. Drive the chisel into the welch plug, push down on chisel and pry plug out of position.

SMALL CHISEL

PIERCE PLUG WITH TIP

SPLIT SYSTEM

GASKET ALIGNMENT MARKER

MAIN NOZZLE BLEED/JET

"O" RING IN GROOVE

SPRING

BOWL

DRAIN

In addition to this, the married system carburetor has the "O" ring, main jet, and spring located behind the drain system.

MARRIED SYSTEM

"O" RING

JET

SPRING

DRAIN SCREW

PRY OUT PLUG

DO NOT ALLOW CHISEL POINT TO STRIKE CARBURETOR BODY OR CHANNEL REDUCER

SMALL CHISEL

WELCH PLUG TO BE REMOVED

ABOUT 1/8" WIDE

After the welch plug is removed from the carburetor it can be soaked in a commercial carburetor cleaner no longer than 30 minutes. Be sure to follow the directions on the container.

NOTE: Always pull the non metallic slip in venture out before soaking in carburetor cleaner.

Reinstall the venture using the main nozzle to align it correctly. The air bleed passages face the air filter.

After the carburetor has been soaked, all passages may be probed with monofilament fishing line and compressed air to open plugged or restricted passages.

GASKET

Page 15

Install a new welch plug over the idle fuel chamber with

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the raised portion up. Use a punch equal to the size of the plug, to flatten the plug. Do not dent or drive the center of the plug below the top surface of the carburetor.

NOTE: To insure a good seal on this plug, we recommend coating the seam with nail polish which is gas resistant.

FLAT END PUNCH

Primer Bulb Service: To remove the primer bulb, grasp the primer bulb with a needle nose pliers and roll the pliers along the air cleaner body. After removing the primer bulb, the retaining ring must be removed. Use a screwdriver to carefully pry the retainer out of the air cleaner body. Do not reuse old bulb or retainer.

NEW WELCH PLUG

SAME DIAMETER OF PLUG

Install the throttle shaft and shutter (use a new shutter screw and dust seal). The scribe mark on the shutter must be in the 12 o’clock position.

NOTE: NEWER STYLE CARBURETORS USE A TORX T-10 SCREW

12 O'CLOCK POSITION

NOTE: THE BREATHER SYSTEM HOSE MUST BE RECONNECTED HERE.

NOTE: If the scribe mark is out of position the shutter may stick.

To rebuild the Float Bowl, refer to the previous section on float bowl service.

Install the carburetor to the engine using a new gasket. The primer passage in the air cleaner body should be cleaned before it is reinstalled over the carburetor.

After the primer bulb is removed, clean the primer passages thoroughly.

Press the new bulb and retainer into position using a deep reach socket as shown.

CAUTION: Wear safety glasses or goggles when removing retainer.

Install air cleaner body over the carburetor using a new gasket.

NOTE: The VLV models use a closed loop breather system. The crankcase breather tube must be reconnected to the air filter body

Page 16

Chapter 3

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GOVERNORS AND LINKAGE

All Tecumseh 4-cycle engines of recent manufacture are equipped with mechanical type governors. As the speed of an engine increases, centrifugal force moves the weights outward, lifting up the governor spool which contacts the governor shaft; this in turn closes the throttle. As engine speed decreases, the weights are pulled inward by the spring which opens the throttle. Thus, the engine speed controls the throttle opening and maintains a certain governed speed.

CENTER FORCE GOVERNOR

SPOOL

RETAINING RING

GEAR ASSY. (GOV.)

WASHER

IDLER GEAR

NOTE: Gear assembly must have .010 - .020 end play after shaft is installed into flange.

VLV TYPE IITYPE I

SPOOL

UPSET RETAINER

SHAFT

GEAR ASSY. (GOV.)

WASHER

TYPE II governors do not use governor retainer clips. The spool is retained by a raised upset on the shaft.

The governor shaft is pressed into the flange or cover to a specific dimension as shown below.

The governor gear on this engine is driven by the crankshaft through an idler gear as shown below.

IDLER GEAR

GOVERNOR SHAFT

IDLER SHAFT

PRESS DEPTH

1.319

1.334

Page 17

Linkage Installation: The solid link is always connected

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from the throttle lever on the carburetor to the lower hole on the governor lever. The shorter bend has to be toward the governor. The governor extension spring is connected with the spring end hooked into the upper hole of the governor lever and the extension end hooked through the speed control lever. To remove the governor spring, carefully twist the extension end counterclockwise to unhook the extension spring at the speed control lever. Do not bend or distort governor extension spring.

TWIST COUNTERCLOCKWISE TO DISCONNECT

GOVERNOR SPRING

Speed Controls: This engine has an adjustable speed control. Never exceed the manufacture’s recommended speeds.

HIGH SPEED ADJUSTMENT COUNTERCLOCKWISE INCREASES SPEED

LOW SPEED ADJUSTMENT COUNTERCLOCKWISE INCREASES SPEED

SHORT BEND

LONG BEND

Governor Adjustment. With engine stopped, loosen the screw holding the governor clamp and lever. Turn the clamp clockwise, then push governor lever connected to the throttle to a full wide open throttle position. Hold the lever and clamp in this position and tighten the screw.

NOTE: Governor adjustment screw will be Torx head (T-10) effective August 1, 1996 for E.C. Compliance.

Page 18

Chapter 4

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STARTERS

REWIND STARTER

DISASSEMBLY PROCEDURE.

1. After removing the rewind assembly from the engine, remove the starter handle by first pulling a length of rope out using the handle, tie a temporary knot in the exposed rope, then untie the knot in handle or pry out the staple.

2. Untie the temporary knot and slowly allow the rope to fully retract into the starter housing and the recoil spring to fully unwind.

3. Place a 3/4'’ deep reach socket under the retainer pawl. Set the rewind on a bench, supported on the socket.

4. Using a 5/16'’ roll pin punch, drive out the center pin.

5. All components that are in need of service should be replaced.

THIS REWIND SPRING IS NOT IN A CANISTER.

Care must be used when handling the pulley because the rewind spring and cover are held together by the bosses in the pulley.

LEFT-HAND KNOT

DOG SPRING

STARTER DOG

RETAINER PIN

REINSTALL RETAINER PIN 1/8" FROM TOP

FRICTION WASHER

RETAINER COVER

SPRING WASHER

ASSEMBLY PROCEDURE.

1. Reverse the above listed procedure keeping in mind that the starter dogs with the dog springs must snap back to the center of the pulley.

2. Always replace the center pin with a new pin upon reassembly. Also place the two new plastic washers between the center leg and retainer pawl. Discard old plastic washer. The new plastic washers will be provided along with the new center pin.

3. Check retainer pawl. If it is worn, bent or damaged in any manner replace upon reassembly.

Install the new center pin in until it is within 1/8 of an inch of the top of the starter.

CAUTION: Driving the center pin in too far will cause the retainer pawl to bend and the starter dogs will not engage the starter cup.

STYLIZED REWIND STARTER WITH PLASTIC RETAINER

Disassembly Procedure

NOTE: Always replace the decal or plug over the roll pin or wedge to prevent moisture infiltration.

RETAINER WEDGE

STARTER HOUSING

STARTER PULLEY SPRING & COVER

DOG SPRING

STARTER DOG

DOG RETAINER

Page 19

2. Untie the temporary knot and slowly allow the rope

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to fully retract into the starter housing and the recoil spring to fully unwind.

3. Remove the decal from the center of the starter housing.

RETAINER WEDGE

4. Use a small Phillips screwdriver or similar tool to pry the retainer legs apart and lift out the retaining wedge.

5. Pinch the legs of the retainer together and pull on the head of the retainer to remove it from the housing.

6. Remove the pulley assembly from the recoil housing.

7. Repair or replace as necessary.

Assembly

1. If replacing the starter rope, see Step 8.

NOTE: EXTREME CAUTION AND APPROPRIATE SAFETY EQUIPMENT MUST BE USED WHEN WORKING WITH RECOIL SPRINGS.

2. Install a new recoil spring if necessary by pushing the new spring out of the holder into the pulley cavity while aligning the outside spring hook into the deep notch in the pulley. Push the spring cover in until seated.

3. Apply a small amount of lithium grease to the inner bore of the center shaft.

LEFT-HAND KNOT

STARTER HOUSING

STARTER PULLEY SPRING & COVER

DOG SPRING STARTER DOG

DOG RETAINER

4. Replace or check that both starter dogs are in the pulley pockets and that the dog springs are hooked on the outer surface of the dog.

5. Pinch the two legs of the plastic retainer together and start into the center shaft hole.

6. Rotate the retainer so the two tabs on the bottom of the part fit between the dog and pulley hub (left side of the dog). Push the retainer in until the leg prongs pop out of the center shaft.

7. Turn the starter over and snap the locking tab between the retainer legs, replace the top decal.

8. Carefully turn the pulley counterclockwise until it stops. Then back the pulley up until the recoil grommet hole and the pulley hole are aligned. Next using a rope with a cauterized end, feed it into the pulley hole. Tie a left handed knot and allow the rope to be drawn into the recoil slowly.

Page 20

12 Volt Electric Starters

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ELECTRIC STARTER REMOVAL. Remove face plate, air cleaner assembly and gas tank. Compress plastic grommet and pull it out of the blower housing. Slide the wire through slot, being careful not to cut the wire insulation. Remove blower housing, remove flywheel (see flywheel section) and inspect ring gear for wear or damage. Replace if necessary (see flywheel section). Remove nuts on both sides of pinion. Drop starter out of back plate and remove ground wire.

Remove, inspect and replace as necessary. Use reverse procedure for assembly. (For ease of assembly assemble armature into brush end frame first.) Place a small amount of light grease such as lubriplate between the drive nut (3) and helix on armature shaft. DO NOT apply lubricant to pinion driver.

END CAP

AND BRUSH

(ASSEMBLY)

CHECK BRUSHES. Before removing armature, check brushes for wear. Make sure brushes are not worn to the point where brush wire bottoms out in the slot of brush holder. Brush springs must have enough strength to keep tension on the brushes and hold them against the commutator. If brushes are in need of change, replace the entire end cap assembly.

DRIVE ASSEMBLY SERVICE. Pinion gear parts should be checked for damage or wear. If the gear does not engage or slips, it should be washed in solvent (rubber parts cleaned with soap and water) to remove dirt and grease, and dried thoroughly. If damaged, replace parts.

PARTS LIST:

1. Retainer ring

2. Dust washer

3. Drive nut

4. Pinion driver

5. Gear

6. Anti-drift spring

7. Spring retainer (spring collapses into retainer)

8. Cup washer (cup washer cupped over retainer spring)

9. Washer (metal)

10. Retainer ring

11. Thrust washer (metal)

12 Washer (plastic)

13. Lock nuts

14. Cap assembly drive end

15. Armature

16. Housing

17. End cap and brush card assembly

18. Bolts

ARMATURE CHECK. If commutator bars are glazed or dirty, they can be turned down in a lathe. While rotating, hold a strip of 00 sandpaper lightly on the commutator, moving it back and forth. (Do not use emery cloth.) Recut grooves between commutator bars to depth equal to the width of the insulators.

Using a continuity tester to make certain no continuity exists between the commutator (copper) and the iron of the armature, rotate armature and check out all commutator bars.

The armature can be thoroughly checked with a growler if available.

Page 21

ELECTRIC STARTER ASSEMBLY

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ATTACH THE GROUND WIRE prior to assembling the electric starter to the baffle, attach the black ground wire to the electric starter through bolt so the the wire extends between the two adjacent end cap prongs (illustration).

Place the starter into the back plate with the ground wire bolt away from carburetor (see picture). Note that the throttle linkage is routed around starter while the governor spring is routed through the end cap prongs (illustration).

STARTER PRONGS

Tighten nuts on starter bolts (see specifications). Place blower housing on engine and slide wires through slot making sure not to cut insulation. Press grommet into hole. Reassemble gas tank, air cleaner assembly and face plate.

ATTACH GROUND WIRE

BATTERY GROUND LEAD ATTACHED TO ELECTRIC STARTER MOTOR STUD BEFORE ELECTRIC STARTER MOTOR IS ATTACHED TO BLOWER HOUSING BAFFLE

Page 22

Chapter 5

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FLYWHEELS

This engine uses one of two types of flywheels. The first type is a cast iron high inertia flywheel. This type of flywheel will have a pressed on steel ring gear if the engine is equipped with an electric starter. The steel ring gear is nonserviceable. The second and most popular style of flywheel is diecast aluminum. The aluminum flywheel features a replaceable plastic fan and a nonserviceable plastic ring gear when equipped with an electric stater. Disconnect battery before servicing.

FLYWHEEL REMOVAL. Remove the ignition module. Remove the brake pressure from the flywheel. The brake can be locked in the disengaged position by placing a pin into one of the aligned holes in the backing plate lever assy.

To remove the flywheel nut, use a flywheel strap wrench (670305) to hold the flywheel, while turning the flywheel nut counterclockwise.

On engines with cored holes (not tapped) use flywheel puller Part No. 670306.

Screw the knock-off (no. 670169) tool down until it touches the flywheel, then back off 1 turn. Using a large screwdriver, pry upward under the flywheel (side opposite the brake) and tap sharply and squarely on the knock-off tool to break the flywheel loose. If necessary rotate flywheel a half turn and repeat until it loosens.

NOTE: Do not attempt to remove flywheel using a jaw type puller on the outer diameter of the flywheel or flywheel breakage will occur.

NOTE: Never use a pry bar with any type of curve on the end. Breather cover damage can result.

DROP PIN THROUGH TO DISENGAGE BRAKE

Lift the starter cup and fan off of the flywheel. (Aluminum flywheel only)

Remove the flywheel using a flywheel puller or knockoff tool.

Page 23

FOR FLYWHEEL REASSEMBLY (INSTALLATION).

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1. Inspect brake pad to be free of dirt, oil or grease. If pad is contaminated, or less than .060'’ at the narrowest point, replace. See flywheel brake section for procedure.

2. Compress brake lever

3. Install flywheel key

4. Install flywheel

5. Install the fan onto the flywheel so the Tecumseh logo on the fan is on the magnet side of the flywheel.

6. Place starter cup into position and torque flywheel nut to specification. Use a strap wrench to hold the flywheel.

MAGNET

LOGO

2. Use of a recoil starter (top or side mounted) with the rope handle on the engine as opposed to within 24 inches of the operator position. This method is acceptable if the mower deck passes the 360 degree foot probe test. A specified foot probe must not contact the blade when applied completely around the entire blade housing. This alternative can be used with engine mounted brake systems and typical bail controls. The blade stops within three seconds after the operator lets go of the blade control bail at the operator position and the engine is stopped.

Tecumseh’s Flywheel Brake System provides consumer safety by shutting down the engine and lawnmower blade within seconds after the operator releases an Engine/Blade control at the handle of the lawnmower.

The Brake Starter Mechanism may be used with either of two options for starting:

1. Manual Rope Start

2. 12 Volt Starter System

Each system requires the operator to start unit behind mower handle in operator zone area. The electric start system also provides a charging system for battery recharge when engine is running.

BRAKE SYSTEM

Tecumseh’s brake system provides a method of meeting compliance standards which became law as of June 30, 1982. There are two additional methods used by equipment manufacturers that also meet compliance standards and they are as follows:

1. B.B.C. Blade Brake Clutch: This system is designed to stop the blade from rotating, in compliance with the 3 second stopping regulation, after operator lets go of the safety bail. This system allows the engine to continue running while stopping the blade. B.B.C. systems are installed by various O.E.M.'s all parts are supplied by them.

NOTE: Electric start systems equipped with a charging system WILL NOT RECHARGE a dead battery. This system is designed to maintain the charge. Before storage and again in spring the battery should be charged with the O.E.M. supplied charger.

BRAKE PAD

GROUND

CLIP

IGNITION GROUND

WIRE

STOPPING THE ENGINE. In the stop position the brake pad is applied to the inside edge of the flywheel; at the same time the ignition system is grounded out.

"BRAKE ON"

Page 24

BRAKE PAD

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BATTERY. Check battery per manufacturer’s recommendations. The charging system on the engine maintains the battery during normal use.

GROUND

CLIP

IGNITION GROUND

WIRE

"BRAKE OFF"

TO START THE ENGINE. In order to restart the engine, the control must be applied. This action pulls the brake pad away from the inside edge of the flywheel and opens the ignition ground switch.

On electric start systems the starter is energized to start the engine.

On non-electric start systems, recoil starter rope must be pulled to start engine.

WIRING DIAGRAMS (Electric Start Systems). All wiring beyond the connectors on the engine are supplied by the equipment manufacturer. Check all terminals and connectors for corrosion and adequate contact, and all wiring for damage and proper size.

When battery is low, use the 120 volt auxiliary charger (usually supplied by the equipment manufacturer).

TO REPLACE BRAKE PAD:

1. If equipped with electric starter, locate wire routing through blower housing. Compress the grommet and pull out of the blower housing. Carefully slide wires through the slot. DO NOT cut the wire insulation on the blower housing.

2. Remove flywheel (see flywheel removal.)

3. Remove pad lever “E” clip. Lift pad lever, and unhook spring and link.

4. Attach the link to the new pad lever, install pad lever and “E” clip.

5. Attach spring to lever first. Use a needle nose pliers to hook the spring into the baffle.

PAD LEVER "E" CLIP

KEYSWITCH CONTROL

IGNITION SHORT-OUT SWITCH

CHARGING RECTIFIER

STARTER MOTOR

(INTERNALLY GROUNDED)

STARTER INTERLOCK SWITCH

ELECTRIC STARTER LEAD

HEAVY DUTY SWITCH

BATTERY (12 VOLT)

RED #12

A.W. G.

IGNITION SHORT-OUT LEAD

BATTERY GROUND

IGNITION SHORT-OUT LEAD

BATTERY GROUND

IGNITION SHORT-OUT LEAD

ALTERNATOR LEAD

BLACK #12

A.W. G.

VIEW A-A

IGNITION

SHORT-OUT

LEAD #13

(OPTIONAL)

RED #12 A.W .G.

RED #18 A.W .G.

A.W. G.

ALTERNATOR

LEAD ELECTRIC STARTER

LEAD

BRAKE LEVER "E"

LONG HOOK

SHORT HOOK

NOTE: It is important to attach the pad lever spring with the short hook on the pad lever and the long hook to the blower housing baffle.

ALL GROUND CONNECTIONS MUST BE CLEANED TO A BRIGHT FINISH.

Page 25

BRAKE LEVER

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CONTROL SPRING

TO REPLACE BRAKE CONTROL LEVER:

1. Mark hole that spring is installed into baffle.

2. Remove “E” clip from brake lever shaft.

3. Lift brake control lever and unhook link. Replace with new lever and reassemble in reverse order.

CONTROL SWITCH. The brake lever must close the switch before the starter can be engaged.

Disconnect battery from circuit before making check.

Engines equipped with an electric starter have a control switch that is attached to the brake lever. The brake lever must close the switch before the starter can be engaged.

CHECKING THE CONTROL SWITCH. Disconnect the battery from the circuit. Use a continuity light or meter to check control switch operation. Disconnect the wire harness at the engine. Attach one continuity light lead to the electric starter lead (see illustration on previous page.) Attach the other continuity light lead to the battery ground lead. With leads attached, press the control switch lever and the continuity light should go on, if not replace switch.

4. Replacement springs must be the same size and color.

5. Be sure control lever spring is in proper hole in blower housing baffle before reassembly.

When removing the brake lever with a reverse pull brake, the pad lever must be removed to unhook the brake link from the brake lever.

BRAKE LEVER CONTROL LINK ATTACHMENT

BRAKE LEVER END

PAD LEVER END

CHECK CONTINUITY

ELECTRIC STARTER CONTROL SWITCH

Page 26

Chapter 6

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ALTERNATOR

LAMINATION SCREWS

ALTERNATOR

COIL

ALTERNATOR. The 350 Milliamp charging system consists of a single alternator coil mounted to one side of the solid state module.

NOTE: This charging system is designed to maintain a charged battery. Most O.E.M.'s supply a trickle charger, which should be used before and after off season storage. Then this system will maintain the charge level under normal use conditions.

Do not operate engine with charging system disconnected. Damage to diode may occur.

CHECKING THE SYSTEM. Connect voltmeter at the battery (should read battery voltage). The battery MUST BE IN CIRCUIT for test to perform properly. Next, start engine -voltage should read higher than when engine is off. If there is a change upward in voltage, the charging system is working. If there is no change in voltage, the alternator should be replaced.

NOTE: Set volt/ohm meter to 0-20 volt D.C. scale for test.

SOLID STATE MODULE

IGNITION COIL

LAMINATION SCREW

TROUBLESHOOTING ELECTRIC START ENGINES.

Following is a list of possible problems and causes.

DEAD BATTERY

Extended storage without charging Excessive cranking Faulty starter Faulty wiring Faulty alternator Faulty battery

BATTERY O.K., ENGINE WON‘T CRANK

Brake cable defective Faulty starter switch Poor electrical connections Faulty starter. See starter section

ENGINE CRANKS SLOWLY

Weak or discharged battery Faulty starter

TROUBLESHOOTING FOR BOTH MECHANICAL AND ELECTRIC START SYSTEMS

IF ENGINE PULLS OR CRANKS HARD

Excessive engine drag due to obstructions under deck. Mower traction drive misadjusted Valve clearance too wide Compression release not functioning Compliance brake is still applied

Maximum compression should be 90 PSI. If compression is higher, de-carbon the valve seat and head area and check valve clearances. Exhaust valve clearance may be set as low as .004'’ if necessary to gain more compression relief. If compression is still above 90 PSI, check compression relief part of camshaft.

Page 27

Chapter 7

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IGNITION

SOLID STATE IGNITION. Tecumseh’s solid state

capacitor discharge ignition (CDI) is an all electronic ignition system and is encapsulated in epoxy for protection against dirt and moisture.

SOLID STATE IGNITION OPERATION. As the magnets in the flywheel rotate past the charge coil, electrical energy is produced in the module. This energy is transferred to a capacitor where it is stored until it is needed to fire the spark plug.

The magnet continues rotating past a trigger coil where a low voltage signal is produced and closes an electronic switch (SCR).

The energy which was stored in the capacitor is now transferred through the switch (SCR) to a transformer where the voltage is increased from 200 volts to 25,000 volts. This voltage is transferred by means of the high tension lead to the spark plug, where it arcs across the electrode of the spark plug and ignites the fuel-air mixture.

SPARK PLUG SERVICE. Spark plugs should be replaced periodically. Check electrode gap with wire feeler gauge and adjust gap to .030". Replace if electrode is pitted, burned or the porcelain is cracked. Refer to Master Parts Manual for correct replacement number. Use a spark plug tester to check for spark.

The proper air gap setting between magnets and the laminations on CDI systems is .0125'’. Place .0125'’ gauge, Part No. 670297 between the magnets and laminations and tighten mounting screws to a torque of 30-40 inch pounds. Recheck gap setting to make certain there is proper clearance between the magnets and laminations. NOTE: Due to variations between pole shoes, air gap may vary from .005/.020'’ when flywheel is rotated. There is no further timing adjustment on external lamination systems.

IGNITION TIMING. The flywheel key is what times the ignition for the engine. If this key is partially sheared from striking an object with the blade. The timing and engine performance could be affected. The key should be inspected if a performance problem exists.

If spark plug fouls frequently, check for the following conditions:

1. Incorrect spark plug

2. Poor grade gasoline

3. Breather plugged

4. Oil level too high

5. Engine using excessive oil

6. Clogged air cleaner

Page 28

Chapter 8

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PISTON, RINGS AND CONNECTING ROD

INDICATES .010 OVERSIZE PISTON

PISTON MEASUREMENTS ARE TAKEN AT

BOTTOM OF SKIRT 900 FROM WRIST PIN HOLE

1ST COMPRESSION RING

SIDE CLEARANCE

2ND COMPRESSION RING

NOTE: EMISSION COMPLIANT VLV USES THIS RING PACKAGE

PISTON. Before removing piston, clean any carbon from the top of the cylinder bore to prevent ring breakage when removing the piston. Push the rod and piston out through the top of the cylinder.

3RD OIL CONTROL RING

BARREL FACED TOP RING

SCRAPER RING

OIL CONTROL RING

CYLINDER

CONNECTING RODS. Match marks on connecting rods must always align and must face outward toward the mechanic when installed in an engine.

PISTON

PISTON RING

MATCH MARKS

Oversize pistons are identified by the size imprinted on the piston as shown. Check the piston for wear by measuring at the bottom of the skirt 90o from the wrist pin hole. Clean the carbon from the piston ring grooves, install new rings and measure side clearance. Tolerances are listed in the table of specifications (page

40).

Replace rings in sets and always stagger ring gaps. When in stalling new rings, deglaze cylinder wall, using a commercially available deglazing tool.

Use a ring expander to remove and replace rings. Do not spread the rings too wide or breakage will result.

The top compression ring will have a chamfer on the inside edge. The ring must be installed with the chamfer up.

To check ring end gap, place ring squarely in center of ring travel area. Using the piston to push the ring down into the cylinder at least one inch.

Check ring gap on new ring to determine if cylinder should be rebored to take oversize parts. See Table of Specifications (page 40).

MATCH MARKS

A new piston can be installed on to the connecting rod in either direction.

If the old piston is reused, install the piston to the connecting rod so that the piston will be in the same position when reinstalled in the engine.

If it is necessary to replace the connecting rod be sure to mark the valve side of the piston.

Page 29

Chapter 9

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CYLINDERS AND CYLINDER HEADS

CYLINDER SERVICE. Check cylinder for dirty, broken

or cracked fins, worn or scored bearings or scored cylinder bore surface, and warped head mounting surface.

If cylinder bore is worn more than .005'’ oversize, out-of round or scored, it should be replaced or rebored to .010 or .020 oversize. In some cases engines are built with an oversize cylinder; in these instances they are identified with the oversize value imprinted on the cylinder as pictured. Service pistons have the oversized valve marked on the dome.

INDICATES .010 OVERSIZE PISTON

.010

CYLINDER HEADS. Check cylinder heads for warpage by placing on a flat surface. If the cylinder head gasket surface is warped in excess of .005 inches (.13 mm), replace head. Always replace head gasket and torque head bolts in 50 inch lb. increments in the numbered sequence to a torque of 180-220 inch lbs. (20.3 - 25 nm)

TORQUE IN NUMERICAL ORDER

REBORING CYLINDER. To rebore cylinder we recommend using a reputable machine shop or service center.

Then hone the cylinder with 380 grit stone to obtain a good cross hatch pattern for proper ring seating.

Clean cylinder with soap and water, and dry thoroughly.

Replace piston and piston rings with correct oversize parts as indicated in parts manual.

Page 30

Chapter 10

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CRANKSHAFTS, CAMSHAFTS

AND LUBRICATION

CRANKSHAFTS. Inspect crankshaft for worn,

scratched or damaged bearing surfaces, out-of-round or flat spots on the journal area, or a bent P.T.O. end.

CAUTION: Never try to straighten a bent crankshaft.

When installing a crankshaft, lubricate all bearing surfaces and use oil seal protector part no. 670327.

CRANKSHAFT TIMING MARK

The crankshaft has a pressed on timing gear. This gear has a small dimple punched on one of the teeth on this gear. This dimple is a timing mark. With the crankpin at top dead center, the timing mark should be in the 2:30 position.

2:30

The camshaft has an aligning mark in line with the timing hole on the camshaft gear. Line this mark up with the dimple on the crankshaft gear.

Timing marks on crankshaft gear and camshaft gear must be aligned for proper valve timing.

CAMSHAFT REMOVAL:

Align timing marks to relieve valve train pressure. Lift out cam.

CRANKSHAFT COUNTERWEIGHT RELIEF

COMPRESSION RELEASE MECHANISM

The camshaft has a mechanical compression release mechanism. A pin which runs through both cam lobes extends past the exhaust lobe and lifts the valve to relieve compression for easier starting. When the engine starts, centrifugal force moves the flyweight outward, moving the pin below the lobe, allowing full compression. The compression release mechanism is nonserviceable (replace camshaft assy. if damaged or worn.)

The camshaft has been relieved in the intake lobe area. This change was made to accommodate added crankshaft counterweight material for improved engine balance.

Page 31

LUBRICATION SYSTEM:

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All Tecumseh Vertical shaft 4-cycle engines use a positive displacement plunger oil pump to pump oil from the crankcase, up through the camshaft to a passage in the breather box to the top crankshaft main bearing, and ultra balance bearings.

Oil is pressure sprayed out of a small hole between the crankshaft and ultra-balance bearing, to lubricate the connecting rod journal area. If a heavy leakage is noted from the breather cover check for plugged mist hole.

FROM CAMSHAFT

CHAMFER UP

OIL PUMP. An eccentric on the camshaft works the plunger in the barrel back and forth, forcing oil up the center of the camshaft. A ball on the end of the plunger locates in a recess in the flange cover. When installing oil pump, make certain the chamfered side of the pump barrel faces the camshaft, and the plunger ball seats in the recess of the flange cover.

OIL PASSAGE

OIL DRAIN

HOLE

OIL MIST HOLE

MAIN BEARING LUBE HOLE

BREATHER OIL RETURN HOLE

This engine has a top mounted integral breather.

OIL RETURN

FILTER ELEMENT

BREATHER TUBE

BREATHER CHECK VALVE

SPRAY MIST HOLE

Page 32

The breather compartment is located under the flywheel.

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A check valve allows excess crankcase pressure to be vented through the element and out the breather tube. The breather tube is connected to the air cleaner body. When reassembling the breather, DO NOT pinch the filter element under the breather cover or leak may occur.

OIL RETURN HOLE

BREATHER TUBE CONNECTION

NOTE: ALWAYS RECONNECT THE BREATHER TUBE

Condensed oil vapors are returned to the crankcase by means of the oil return hole. The oil return hole is opened and closed in the cylinder by the piston.

The breather filter element can be cleaned using solvent.

When reinstalling the check valve, apply oil to aid in assembly. A new breather valve body can be pressed into the block to replace a damaged breather valve body.

Page 33

Chapter 11

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VALVES, LIFTERS, SPRING & VALVE SEATS

VALVES. Valves must be in good condition, proper

sealing and proper gap must be maintained for full power, easy starting and efficient operation.

VALVE REMOVAL. To remove valves, use a commercially available valve spring compressor. Move the lower cap, so it will slip off the end of the valve.

Clean all parts and remove carbon from valve heads and stems. If valves are in usable condition, grind the valve faces to a 45o angle. Replace valves if they are damaged, distorted or if the margin is ground to less than 1/32'’.

MARGIN

1/32" MINIMUM

DIMENSION

STEM

FACE

BOTTOM

NARROWING

CUTTER

SEAT

BOTTOM

NARROWING

Second, use the 31o cutter to clean and narrow the seat from the top toward the center.

TOP

NARROWING

CUTTER

SEAT

VALVE SEATS. Valve seats are not replaceable. If they are burned or pitted, they can be reground using a grinding stone or valve seat cutter.

EXHAUST VALVE

INTAKE VALVE

SEE SPECIFICATIONS SECTION FOR DIMENSIONS

The recommended procedure to properly cut a valve seat is to use the Neway Valve Cutting System, which consists of three different degree-cutters. First, use the 60o cutter to clean and narrow the seat from the bottom toward the center.

Seats are ground at an angle of 46o, to a width of 3/64'’.

SEAL CUTTER

3/64"

SEAT

Valves are not identical. Make sure the valve marked “EX” or “X” is installed in the exhaust valve location, and the valve marked “I” is installed in the intake valve location. If the valves are unmarked, the nonmagnetic valve is installed in the exhaust valve location.

Page 34

FACE

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WRONG

RIGHT

VALVE ADJUSTMENT. Clearance between the valve stem and lifter must be set to the recommended specifications when the engine is cold (see page 40). Check these clearances with the piston T.D.C. on the compression stroke. Grind end of valve stem with a valve grinder, or use a “V” block to hold the valve square on grinding wheel, grinding to the proper .004" to .008” clearance.

NOTE: Some emissionized engines use intake valve stem seals to maintain proper oil control and emission compliance, they must be replaced if the valve has been removed.

VALVE LIFTERS. It is a good practice not to interchange lifters, even though they are identical, once a wear pattern has been established.

OVERSIZE VALVE GUIDES. Valve guides are permanently installed in the cylinder. If they become worn excessively, they can be reamed oversized to accommodate a 1/32'’ over size valve stem.

Ream guides with a straight shanked hand reamer or low speed drill press. Refer to Table of Specifications to determine correct oversize dimension. Reamers are available through your Tecumseh parts suppliers. See Tool Section for correct part numbers.

After oversizing valve guides the seats must be recut to align with the valve guides.

VALVE INSTALLATION. To reinstall valves, position valve caps and spring in the valve compartment. Install valves in guides with valve marked “I” in the intake port. The valve stem must pass through the spring. The valve spring cap should sit around the valve lifter exposed end. Use a valve spring compressor to compress the valve spring. Position the valve spring cap onto the valve stem and release valve spring tension to lock cap in place.

Page 35

Chapter 12

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OIL SEAL SERVICE AND MOUNTING FLANGE

OIL SEAL SERVICE. Drain oil from crankcase. If the

crankshaft end is rusty or pitted, polish the crankshaft with emery cloth so it will not damage the bearings when the cover is removed.

Remove mounting bolts and slide seal protector-driver tool (Part No. 670327) into the oil seal. If necessary, tap edge of flange or cover lightly with a soft hammer to remove cover.

Clean and inspect the cover for wear and scoring of bearings. Inspect crankshaft bearings. Replace any worn or damaged parts.

MOUNTING FLANGE

SEAL PROTECTOR DRIVER

If crankshaft is out of engine, remove old oil seals by tapping them out with a screwdriver or punch from the inside. To remove a seal with the crankshaft in the engine, insert a screwdriver between the seal and the crankshaft and pry the seal out.

TO REPLACE SEALS: Lubricate the outside of the new oil seal with oil prior to installation. Use seal driverprotector tool Part No. 670327. Place oil seal over the driver-protector and place over crankshaft, driving it into position using universal driver No. 670272. The seal will automatically be driven into the proper depth.

Torque flange bolts in numerical order as shown in illustration. See page 41 for torque specifications.

Page 36

Chapter 13

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TROUBLESHOOTING

A. COMMON TROUBLES AND REMEDIES.

The following charts list the most common troubles experienced with gasoline engines. Possible causes of trouble are given along with probable remedy.

B. 4-CYCLE ENGINE TROUBLESHOOTING CHART

Cause Remedy and Reference

ENGINE FAILS TO START OR STARTS WITH DIFFICULTY

No fuel in tank Fill tank with clean, fresh fuel.

Shut-off valve closed Open valve.

Obstructed fuel line Clean fuel screen and line. If necessary, remove and clean

carburetor.

Incorrect Timing Flywheel key has sheared or partially sheared. Replace key.

Tank cap vent obstructed Clean the vent or replace the cap.

Water in fuel Drain tank. Clean carburetor and fuel lines. Dry spark plug

points. Fill tank with clean, fresh fuel.

Engine flooded Close fuel shut-off, if so equipped, and pull starter until engine

starts. Reopen fuel shut-off for normal fuel flow.

Loose or defective ignition wiring Check ignition wiring for shorts or grounds; repair if

necessary.

Spark plug fouled Replace spark plug.

Spark plug porcelain cracked Replace spark plug.

Poor Compression Overhaul engine.

No spark at plug Check ignition air gap. If air gap is correct and there is no

spark at plug replace ignition.

Electric starter does not crank engine See 12 volt starter troubleshooting chart.

ENGINE KNOCKS

Carbon in combustion chamber Remove cylinder head and clean carbon from head and

piston.

Loose or worn connecting rod Replace connecting rod.

Loose flywheel Check flywheel key and keyway; replace parts if necessary.

Tighten flywheel nut to proper torque.

Worn cylinder Replace cylinder.

Improper ignition timing Flywheel key has sheared or partially sheared. Replace key.

Page 37

4-CYCLE ENGINE TROUBLESHOOTING CHART (Cont.)

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Cause Remedy and Reference

ENGINE MISSES UNDER LOAD

Spark plug fouled Replace spark plug.

Spark plug porcelain cracked Replace spark plug.

Improper spark plug gap Regap spark plug.

Improper valve clearance Adjust valve clearance to recommended specifications.

Weak valve spring Replace valve spring.

ENGINE LACKS POWER

Ignition improperly timed Replace flywheel key.

Worn rings Replace rings.

Lack of lubrication Fill crankcase to the proper level.

Air cleaner fouled Service air cleaner.

Valves leaking Grind valves and set to recommended specifications.

ENGINE OVERHEATS

Engine improperly timed Replace flywheel key if sheared.

Air flow obstructed Remove any obstructions from air passages in shrouds.

Cooling fins clogged Clean cooling fins.

Excessive load on engine Check operation of associated equipment. Reduce

excessive load.

Carbon in combustion chamber Remove cylinder head and clean carbon from head and

piston.

Lack of lubrication Fill crankcase to proper level.

ENGINE SURGES OR RUNS UNEVENLY

Fuel tank cap vent hole clogged Open vent hole.

Governor parts sticking or binding Clean, and if necessary repair governor parts.

Carburetor throttle linkage or throttle shaft Clean, lubricate, or adjust linkage and deburr throttle shaft and/or butterfly binding or sticking or butterfly.

Intermittent spark at spark plug Disconnect ignition cut-off wire at the engine. Crank

engine. If spark, check ignition switch, safety switch and interlock switch. If no spark, check ignition air gap. Check wires for poor connections, cuts or breaks.

Dirty carburetor Clean carburetor.

ENGINE VIBRATES EXCESSIVELY

Engine not securely mounted Tighten loose mounting bolts.

Bent crankshaft Replace crankshaft.

Associated equipment out of balance Check associated equipment.

Page 38

4-CYCLE ENGINE TROUBLESHOOTING CHART (Cont.)

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Cause Remedy and Reference

ENGINE USES EXCESSIVE AMOUNT OF OIL

Engine speed too fast. Using tachometer adjust engine RPM to spec.

Oil level too high. To check level turn dipstick cap tightly into receptacle for

accurate level reading.

Oil filler cap loose or gasket damaged causing Replace ring gasket under cap and tighten tube securely. spillage.

Breather mechanism damaged or dirty causing Replace breather assembly. leakage.

Drain hole in breather box clogged causing oil to Clean hole with wire to allow oil to return to crankcase. spill out of breather.

Gaskets damaged or gasket surfaces nicked Clean and smooth gasket surfaces. Always use new causing oil to leak out. gaskets.

Valve guides worn excessively thus passing oil Ream valve guide oversize and install 1/32'’ oversize valve into combustion chamber. and new valve seal if equipped.

Cylinder wall worn or glazed, allowing oil to Bore cylinder for oversized piston & rings. bypass rings into combustion chamber.

Piston rings and grooves worn excessively. Reinstall new rings and check land clearance and correct

as necessary.

Piston fit undersized. Measure and replace as necessary.

Piston oil control ring return holes clogged. Remove oil control ring and clean return holes.

Oil passages obstructed. Clean out all oil passages.

Breather tube not connected to air cleaner. Reconnect tube.

Using 10W30 oil under high load/high temperature Replace with SAE 30 oil. conditions.

OIL SEAL LEAKS

Crankcase breather plugged. Clean or replace breather.

Seal/Main brg drain hole plugged. Clean out hole.

Old seal hardened and worn. Replace seal.

Crankshaft seal contact surface is worn undersize Check crankshaft size and replace if worn excessively. causing seal to leak.

Crankshaft bearing under seal is worn excessively, Check crankshaft bearings for wear and replace if causing crankshaft to wobble in oil seal. necessary.

Seal outside seat in cylinder or side cover is Visually check seal receptacle for nicks and damage. damaged, allowing oil to seep around outer Replace P.T.O. cylinder cover, or small cylinder cover on edge of seal. the magneto end if necessary.

Page 39

4-CYCLE ENGINE TROUBLESHOOTING CHART (Cont.)

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Cause Remedy and Reference

OIL SEAL LEAKS

New seal installed without correct seal driver and Replace with new seal, using proper tools and methods. not seating squarely in cavity.

New seal damaged upon installation. Use proper seal protector tools and methods for installing

another new seal.

Bent crankshaft causing seal to leak. Check crankshaft for straightness and replace if

necessary.

Oil seal driven too far into cavity. Remove seal and replace with new seal, using the correct

driver tool and procedures.

BREATHER PASSING OIL

Engine speed too fast. Use tachometer to adjust correct RPM.

Loose oil fill cap or gasket damaged or missing. Install new ring gasket under cap and tighten securely.

Oil level too high. Check oil level Turn dipstick cap tightly into receptacle for

accurate level reading. DO NOT fill above full mark.

Breather mechanism damaged. Replace umbrella valve/seat in Vector engine and TVS

engines.

Breather mechanism dirty. Clean thoroughly in solvent. Use new gaskets when

reinstalling unit.

Drain hole in breather box clogged. Clean hole with wire to allow oil to return to crankcase.

Breather mechanism installed upside down. Small oil drain holes must be down to drain oil from

mechanism.

Breather mechanism loose or gaskets leaking. Install new gaskets and tighten securely.

Damaged or worn oil seals on end of crankshaft. Replace seals.

Rings not properly seated. Check for worn, or out of round cylinder. Replace rings.

Break in new rings with engine working under a varying load. Rings must be seated under high compression, or in other words, under varied load conditions.

Breather assembly not assembled correctly. See section on Breather Assembly.

Cylinder cover gasket leaking. Replace cover gasket.

Page 40

C. TROUBLESHOOTING CARBURETION.

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POINTS TO CHECK FOR CARBURETOR MALFUNCTION

TROUBLE CORRECTIONS

Engine will not start 1, 2, 3, 4, 5, 6, 8, 14, 15, 17

Engine will not accelerate 2, 3, 17

Engine hunts (at idle or high speed) 3, 4, 8, 9, 14

Engine will not idle 4, 8, 9, 14

Engine lacks power at high speed 2, 3, 6, 8, 17

Carburetor floods 4, 7, 16

Carburetor leaks 6, 7

Engine overspeeds 8, 9, 14, 15

Idle speed is excessive 8, 9, 14, 15

Choke does not open fully 8, 9, 15

Engine starves for fuel at high speed (leans out) 1, 3, 4, 6, 15, 16, 17

Carburetor runs rich with main adjustment needle shut off 7, 16

Performance unsatisfactory after being serviced. 1, 2, 3, 4, 5, 6, 7, 8, 9, 15, 16, 17

1. Open fuel-shut off valve at fuel tank—Fill tank with fuel.

2. Check ignition, spark plug.

3. Clean air cleaner—Service as required.

4. Dirt or restriction in fuel system—Clean tank and fuel strainers, check for kinks or sharp bends.

5. Check for stale fuel or water in fuel - - Fill with fresh fuel.

6. Examine fuel line and pick-up for sealing at fittings.

7. Check and clean atmospheric vent holes.

8. Examine throttle for binding or excessive play- Remove all dirt or paint, replace shaft.

9. Examine throttle return spring for operation.

10. Check for bent throttle plate.

11. Adjust control cable or linkage, to assure carburetor control.

12. Clean carburetor after removing all nonmetallic parts that are serviceable. Trace all passages.

13. Check inlet needle and seat for condition and proper installation.

14. Check sealing of welch plugs, and gaskets.

15. Adjust governor linkage.

16. Check float shaft for wear and float for leaks or dents.

17. Check flywheel key for damage.

Page 41

D. TROUBLESHOOTING 12 VOLT STARTERS

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PROBLEM PROBABLE CAUSE FIX

Does not function Weak or dead battery Check charge and/or replace battery.

Corroded battery terminals and/or Clean terminals and/or connections. electrical connections

Brushes sticking Free brushes. Replace worn brushes and

those which have come in contact with grease and oil.

Dirty or oily commutator Clean and dress commutator.

Armature binding or bent Free armature and adjust end play, replace

armature, or replace starter.

Open or shorted armature Replace armature.

Shorted, open or grounded field coil Repair or replace housing.

Loose or faulty electrical connections Correct.

Load on engine Disengage brake.

Electric starter cranks, but no spark Disconnect ignition cut-off wire at the engine. at spark plug Crank engine. If spark at spark plug, ignition

switch, safety switch is in operative. If no spark, check air gap. Check wires for poor connections, cuts or breaks.

Electric starter does not crank engine Remove starter wire. Use a jumper battery

and cables and attach directly to starter wire. If starter cranks engine the starter is okay, check solenoid, starter switches, safety switches and interlock switch. Check wires for poor connections, cuts or breaks.

Electric starter cranks, but engine Check flywheel ring gear for broken teeth. does not turn over. Replace flywheel if necessary.

Low RPM Unit controls engaged Insure all unit controls are in neutral or

disengaged.

Worn bearings in cap assemblies Clean bearings or replace cap assemblies.

Bent armature Replace armature.

Binding armature Free up armature. Adjust armature end play.

Brushes not seated properly Correct.

Weak or annealed brush springs Replace springs.

Incorrect engine oil Ensure the correct weight of oil is being

used.

Dirty armature commutator Clean commutator.

Shorted or open armature Replace armature.

Loose or faulty electrical connections Correct. in motor

Page 42

TROUBLESHOOTING 12 VOLT STARTERS (Cont.)

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PROBLEM PROBABLE CAUSE FIX

Motor stalls under load Shorted or open armature Replace armature.

Shorted field coil Correct, or replace housing assembly.

Intermittent operation Brushes binding in holders Free up brushes. Replace worn brushes

and those which have come in contact with grease and oil.

Dirty or oily commutator Clean and dress commutator.

Loose or faulty electrical Correct connections

Open armature Replace armature and interlock switch.

Break in electrical circuit Disconnect ignition cut-off wire at the

engine. Crank engine, if spark, check ignition switch, safety switch and interlock switch. Check wires for poor connections, cuts or breaks.

Sluggish disengagement Dirt and oil on assembly and Clean drive assembly and armature shaft of the drive assembly armature shaft and relubricate shaft splines. pinion gear

Bent armature Replace armature.

Page 43

Chapter 14

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ENGINE SPECIFICATIONS

VLV40 VLV50, 55, 60, 65

Displacement 11.19 183.4 cc 12.6 207 cc

Stroke 2.047 51.993 mm 2.047 51.993 mm

Bore 2.6390 67.031 mm 2.796 71.018 mm

Air Gap Dimension Ignition .0125 .30 mm .0125 .30 mm

Spark plug gap .030 .70 mm .030 .70 mm

Valve Clearance Intake and Exhaust .004 .101 mm .004 .101 mm

Valve Seat Angle 46

Valve Seat Width .047 1.2 mm .047 1.2mm

Valve Guide Oversize Dia. .2807 71.297 mm .2807 71.297 mm

Crankshaft End Play .005 .127 mm .005 .127 mm

Crankpin Journal Dia. 1.0235 25.996 mm 1.0235 25.996 mm

Crankshaft Magneto Main Brg. Dia 1.0242 26.014 mm 1.0242 26.014 mm

Crankshaft P.T.O. Main Brg. Dia 1.0242 26.014 mm 1.0242 26.014 mm

2.6380 2.795 70.993 mm

.008 .203 mm .008 .203 mm

.2817 71.551 mm .2817 71.551 mm

.027 .685 mm .027 .685 mm

1.0230 25.984 mm 1.0230 25.984 mm

1.0237 26.001 mm 1.0237 26.001 mm

Camshaft Bearing Dia. .4980 12.649 mm .4980 12.649 mm

Conn. Rod Dia. Crank Brg. 1.0246 26.024 mm 1.0246 26.024 mm

Piston Diameter 2.6340 66.903 mm 2.6340 66.903 mm

Ring Groove Side Clearance 1st & 2nd Comp. .002 .050 mm .002 .050 mm

Side Clearance (Bot.) Oil .0005 .012 mm .0005 .012 mm

Piston Skirt Clearance measured 90 at the bottom of the skirt .006 .152 mm .006 .152 mm

Ring End Gap .007 .177 mm .007 .177 mm

Cylinder Main Brg. Dia 1.0262 26.065 mm 1.0262 26.065 mm

Cylinder Cover/Flange Main Bearing Diameter 1.0262 26.065 mm 1.0262 26.065 mm

from pin .004 .101 mm .004 .101 mm

.4975 12.636 mm .4975 12.636 mm

1.0240 26.009 mm 1.0240 26.009 mm

2.6330 66.878 mm 2.6330 66.878 mm

.005 .127 mm .005 .127 mm

.0035 .088 mm .0035 .088 mm

.020 .508 mm .020 .508 mm

1.0257 26.052 mm 1.0257 26.052 mm

Page 44

TORQUE SPECIFICATIONS

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Inch-Lbs. Nm

Governor Rod Clamp to Lever 7-12 1.4 - 1.4

Breather Cover 40-50 4.5 - 5.7

Valve Box Cover 25-35 3.1 - 4.0

Connecting Rod 95-110 10.7 - 12.4

Cylinder Head 180-220 20.3 - 25

Mounting Flange or Cylinder Cover 100-130 11.3 - 14.7

Housing Baffle to Cylinder 80-120 9.0 - 13.6

Solid State Ignition to Cylinder 30-50 3.4 - 5.7

Alternating Coil Assembly to Lamination 25-35 2.8 - 4.0

Flywheel Nut 400-440 45.2 - 49.7

Housing to Baffle 35-45 4.0 - 5.1

Carburetor Stud to Cylinder 50-75 5.7 - 8.5

A/C Hex Nut to Stud 35-45 4.0 - 5.1

Control Face Plate to Baffle 30-40 3.4 - 4.5

Starter Top Mounting 20-30 2.3 - 3.4

Electric Starter to Baffle 25-35 2.8 - 3.9

5/8-18 Plug (Hex Flange) Drain plug 90-150 10.2 - 17.0

Plastic Tank to Housing 12-20 1.4 - 2.3

Threaded Fill Tube (Plastic) 45-65 4.0 - 7.3

Large Diameter Oil Fill Plug Hand Tight

Muffler Mounting (Shoulder Screw) 100-165 11.3 - 18.7

A/C Body & Housing to Baffle 35-45 4.0 - 5.1

Conduit Clip Screw (Throttle Cable) 5-15 .6 - 1.7

Muffler Deflector 10-15 1.1 - 1.7

Page 45

Chapter 15

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TRAINING AIDS AND TOOLS

VIDEO PROGRAMS

695015

Carburetor Troubleshooting. Covers identification of carburetors used on Tecumseh engines and how to troubleshoot and repair them. VHS only.

695059

Understanding Tecumseh Ignition Systems. A basic program designed to give the small engine technician first hand knowledge of Tecumseh ignition systems so the technician can understand the system and perform repairs to it. VHS only.

695148

Teardown and reassembly of the 900 series transaxles. This video will show a complete step-by-step procedure for teardown and reassembly of the 900, 910 and 920 series transaxles.

695185

Electrical Troubleshooting. This video training program will assist the small engine technician in the proper procedures for troubleshooting electrical systems on outdoor power equipment.

695285

An in-depth look at the 800 series transaxles. Detailing the teardown and reassembly procedures for the 800, 801 and 820 transaxles.

SPECIAL BOOKLETS

INSTRUCTIONAL GUIDE

692738

Assists in the use and understanding of the Tecumseh Master Parts Manual. Illustrates time saving features incorporated into the manual. Explains new carburetor parts breakdown format.

4-CYCLE ENGINE FAILURE ANALYSIS

695590

This booklet is designed as a tool for the average technician to correctly assess the cause of failure.

ELECTRICAL TROUBLESHOOTING BOOKLET 693505A

This booklet contains schematic drawings of Tecumseh direct current and alternating current systems and how to check them when problems occur.

CARBURETOR TROUBLESHOOTING BOOKLET 695907

This booklet is designed as a quick reference to carburetion problems and related repair procedures.

IGNITION SYSTEMS TROUBLESHOOTING BOOKLET 694903

This booklet contains information on the identification, possible problems and related repair procedures of Tecumseh Ignition Systems.

SPECIAL TOOLS BOOKLET 694862

This booklet depicts all specialty tools offered by Tecumseh which can be used on 2 and 4 cycle engines and Peerless units.

QUICK REFERENCE CHART BOOKLET 695933

This booklet contains the quick reference information found on Tecumseh wall charts. This booklet is designed to be used as a work bench quick reference guide when servicing Tecumseh engines and motion drive systems.

TESTER BOOKLETS 694529

Test procedures for Tecumseh electrical components using GrahamLee Tester 31-SM or 31-SMX-H.

694530

Test procedures for Tecumseh electrical components using Merco-OTronic Tester 9800. (Tests are similar for 98, 98A and 79.)

Page 46

TOOLS

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TOOL KIT 670195C

Kit contains tools for 2- and 4-cycle engines.

Includes all items on this page but items may be purchased separately.

KNOCK-OFF TOOL

670103

VALVE SPRING COMPRESSOR FOR

OVM, OVXL120-125, OHV11-13

670315A

VALVE SPRING COMPRESSOR

FOR OH ENGINE

KNOCK-OFF TOOL

670169

AIR GAP GAUGE .0125"

670253A

CARBURETOR FLOAT

SETTING TOOL

670297

Page 47

FLYWHEEL KNOCK-OFF TOOL

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TORX DRIVERS

Torx 8 670334

Torx 10 670333

Torx 15 670323

Torx 20 670324

No. 670169

VIBRATION TACHOMETER

No. 670156 - Vibration tachometer.

Torx 25 670319

Torx 30 670320

No. 670117 - Ring Expander

No. 670327 - Seal Protector Driver

No. 670339 - E-5 Socket

No. 670283 - Valve Guide Reamer

Page 48

Chapter 16

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SEARS CRAFTSMAN

CROSS REFERENCE CHART

143.434112 VLV55-501004

143.434252 VLV55-501008

143.945500 VLV55-501004A

143.956000 VLV60-502003A

143.956002 VLV60-502004A

143.956006 VLV60-502012A

143.966000 VLV60-502015B

143.966006 VLV60-502023B

143.966008 VLV60-502024B

143.966500 VLV65-502501A

143.966502 VLV65-502502A

143.966504 VLV65-502503A

143.966506 VLV65-502504A

143.966508 VLV65-502505A

143.976000 VLV60-502015C

Page 49

DECIMAL/FRACTION CONVERSIONS

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.016 = 1/64 .031 = 1/32 .047 = 3/64 .063 = 1/16 .078 = 5/64 .094 = 3/32 .109 = 7/64 .125 = 1/8 .141 = 9/64 .156 = 5/32 .172 = 11/64 .188 = 3/16 .203 = 13/64 .219 = 7/32 .234 = 15/64 .25 = 1/4

.516 = 33/64 .531 = 17/32 .547 = 35/64 .563 = 9/16 .578 = 37/64 .594 = 19/32 .609 = 39/64 .625 = 5/8 .641 = 41/64 .656 = 21/32 .672 = 43/64 .688 = 11/16 .703 = 45/64 .719 = 23/32 .734 = 47/64

.75 = 3/4 .266 = 17/64 .281 = 9/32 .297 = 19/64 .312 = 5/16 .328 = 21/64 .344 = 11/32 .359 = 23/64 .375 = 3/8 .391 = 25/64 .406 = 13/32 .422 = 27/64 .438 = 7/16 .453 = 29/64 .469 = 15/32 .484 = 31/64 .50 = 1/2

.766 = 49/64

.781 = 25/32

.797 = 51/64

.813 = 13/16

.828 = 53/64

.844 = 27/32

.859 = 55/64

.875 = 7/8

.891 = 57/64

.906 = 29/32

.922 = 59/64

.938 = 15/16

.953 = 61/64

.969 = 31/32

.984 = 63/64