National Mower HYDRO HY70OM-8-992, HYDRO HYD70OM-8-99 User Manual

1.26 Mb
Loading...

HYDRO 70" TRIPLEX

OWNER'S MANUAL

Includes Assembly, Maintenance &

Parts Lists

For Serial Numbers 1586 & Up

NATIONAL MOWER CO.

700RaymondAve.,P.O.Box14299,St.Paul,Minnesota 55114-0299, U.S.A.

Phone (651) 646-4079 – Fax (651) 646-2887

HYD70OM-8/99

DECLARATION OF CONFORMITY

according to Directive 89/392/EEC

We NATIONAL MOWER COMPANY

..............................................................................................................................................................

(Name of supplier)

700 Raymond Avenue, St. Paul, Minnesota 55114 U.S.A.

..............................................................................................................................................................

(Full address of the manufacturer—authorized representative in the community must also give the business name and address of the manufacturer)

declare under our sole responsibility, that the product

NATIONAL HYDRO 70" TRIPLEX MOWER

(Make and model)

to which this declaration relates corresponds to the relevant basic safety and health requirements of the Directive 89/392/EEC, (if applicable)

and to the requirements of other relevant Directives:

EN292-1&2--EN294--EN349

..............................................................................................................................................................

(Title and/or number and date of issue of the other Directives)

(If applicable)

For the relevant implementation of the safety and health requirements mentioned in the directives, the following standard(s) and/or technical specification(s) has (have) been respected:

ANSI B71.4

..............................................................................................................................................................

(Title and/or number and date of issue of standard(s) and/or technical specification(s))

8/1/99

..............................................................................................................................................................

(Place and date of issue) (Name, function and signature of the authorized person)

2

HY70OM-8/99

NATIONAL® HYDRO 70" TRIPLEX

IMPORTANT

National Mower Safe Operation Practices

For Riding Mowers

1.Know control functions and how to stop quickly. READ THE OWNER’S MANUAL.

2.Do not allow children to operate the mower. Do not allow adults to operate the mower without proper instruction.

3.Do not carry passengers. Keep children and pets at a safe distance from an operating mower.

4.Clear the work place of objects which might be picked up by the blades and thrown.

5.To start engine, operator must be seated, reel control must be disengaged and foot control must be in neutral.

6.Takeallpossibleprecautionswhenleavingthemowerunattended,suchasshiftingintoneutral,stopping the engine and removing the ignition key.

7.Donotstoporstartsuddenlywhengoinguphillordownhill. Useextremecautionwhenmowingonslopes.

8.Reducetravelspeedonslopesandinsharpturnstopreventtippingorlossofcontrol. Useextremecaution when changing direction on slopes.

9.Watch for holes in the terrain and other hidden hazards.

10.Watch for dangerous traffic when crossing or near roadways.

11.Never direct the discharge of material from operating reels toward bystanders nor allow anyone near the mower during operation.

12.Handle gasoline with CAUTION - it is highly flammable.

a.Use an approved gasoline container.

b.Never fill the fuel tank indoors. Wipe spilled gas immediately.

c. Open garage doors to allow ventilation if engine is run inside-exhaust fumes are dangerous. Do not run engine in any enclosed area.

13.Keep the mower in good operating condition. Make sure that all safety switches are operating properly and all safety guards are in place at all times, except during servicing.

14.Keep all nuts, bolts and screws tight to be sure that the mower is in a safe working condition.

15.Never store the mower, with gasoline in the tank, inside a building where the fumes could reach an open flame or spark. Allow the engine to cool before storing in any enclosure.

16.Keep the engine free of grass, leaves or excessive grease to reduce a fire hazard.

17.The mower and reels should be stopped and inspected for damage after striking a foreign object. The damage should be repaired before restarting and operating the mower.

18.Do not change the engine governor settings or over speed the engine.

19.Proceed as follows when mowing.

a.Mow only in the daylight or in good artificial light.

b.Never make a cutting height adjustment while the engine (motor) is running.

c.Shut the engine (motor) off when removing grass or unclogging reels.

WARNING– California, USA residents are required by law (CA PRC 4442 & CA H & SC 13005) to equip their engines with spark arresters when operating in flammable vegitation. Arresters must be obtained from your engine dealer and are not available from National Mower Company.

3

TABLE OF CONTENTS

Declaration Of Conformity .............................................................................

2

Safe Operating Practices ..............................................................................

3

Introduction ...................................................................................................

5

Receipt of Shipment ......................................................................................

5

Specifications ............................................................................................

6-9

Engine Specifications ............................................................................

6

Transmission ..........................................................................................

6

Vehicle Specifications ............................................................................

6

Battery ...................................................................................................

6

Mower Specifications .............................................................................

6

Weight and Dimensions .........................................................................

6

Lubricants ..............................................................................................

6

DisposalNumbers ..................................................................................

7

Noise Emission and Vibration .................................................................

7

Decals .................................................................................................

7-8

Assembly Instructions ..............................................................................

9-10

General Information .........................................................................

11-12

Engine..................................................................................................

11

Traction Drive Train ..............................................................................

11

Reel Drive ............................................................................................

11

Ignition Switch ......................................................................................

11

Hour meter ...........................................................................................

11

Ammeter...............................................................................................

11

ReelControl .........................................................................................

11

Choke ..................................................................................................

12

ThrottleLever .......................................................................................

12

Traction Pedal ......................................................................................

12

Mow and Lift Treadle ............................................................................

12

Free Wheeling Valve ............................................................................

12

Drop/Lift Needle Valve ..........................................................................

12

Interlock Switches ................................................................................

12

Operation ....................................................................................................

13

Adjustments .................................................................................................

13

Traction Pedal ......................................................................................

13

Reel Control Clutch ........................................................................

13, 14

Seat Switch ..........................................................................................

14

Height of Cut ........................................................................................

14

Reel to Bedknife ...................................................................................

15

Reel End Play ......................................................................................

15

Backlapping Procedure ..................................................................

15, 16

Grinding Procedure ..............................................................................

16

Maintenance ...............................................................................................

17

General ................................................................................................

17

Assembly and Disassembly ..................................................................

17

Battery ...........................................................................................

17, 18

Charging a Battery ...............................................................................

18

Bed Knife Replacement ........................................................................

18

Fuel filter ..............................................................................................

18

Engine..................................................................................................

18

Electrical System .................................................................................

18

Hydraulic Hoses ...................................................................................

19

Hydraulic Oil.........................................................................................

19

Hydraulic Oil Filter ................................................................................

20

HandleBarRemoval .............................................................................

20

Jumper Cables .....................................................................................

20

4

HY70OM-8/99

 

®

 

NATIONAL HYDRO 70" TRIPLEX

Lubrication ...........................................................................................

20

Painting ................................................................................................

20

BeltReplacement ...........................................................................

20, 21

CouplingAlignment ..............................................................................

21

Storage .......................................................................................................

22

General Instructions .............................................................................

22

Engine..................................................................................................

22

Battery .................................................................................................

22

Tractor .................................................................................................

22

Tires .....................................................................................................

22

Starting After Storage ...........................................................................

22

Trouble Shooting Guide ...............................................................................

23

Engine Will Not Start ............................................................................

23

Tractor Will Not Move ...........................................................................

23

Reel Not Turning...................................................................................

23

Reel Will Not Cut ..................................................................................

23

Lubrication .....................................................................................

24, 25

Electrical Schematic.............................................................................

26

Parts List and Ordering Information.............................................................

27

Tank and Rear Fork Assembly .......................................................

28, 29

Steering Tower Assembly ...............................................................

30, 31

Engine and Footrest Assembly .......................................................

32, 33

Traction Pedal and Pump Assembly ...............................................

34, 35

Lift Arm and Drive Assembly ..........................................................

36, 37

Front Cutting Unit Assembly ...........................................................

38, 39

Rear Cutting Unit Assembly ............................................................

40, 41

Hydraulic Hose and Line Assembly ................................................

42, 43

Hydraulic Fitting Assembly .............................................................

44, 45

BasketAssembly ..................................................................................

46

BeltToo ...............................................................................................

l46

Height Of Cut Bar .................................................................................

47

Pump ...................................................................................................

47

Wheel Motor.........................................................................................

48

Lift Valve ..............................................................................................

48

Lift Cylinder ..........................................................................................

49

Front Roller Scraper Kit ........................................................................

49

Rear Roller Scraper Kit ........................................................................

50

ValveBlock ..........................................................................................

50

Warranty .....................................................................................................

51

1—INTRODUCTION

This manual has been prepared by National Mower Company as an aid to users for assembly, maintenance, adjustment and ordering replacement parts. Additional information will gladly be furnished by calling or writing National Mower Company.

Please furnish us with the Model Number, Serial

Number and Date of Purchase when contacting us about your machine. Designations of right, left, front and rear are used as if the operator was sitting in the mower seat.

2—RECEIPT OF SHIPMENT

Carefully inspect your machine and crate for damage that could have occured during shipment. If damages or shortages are noted, have the transportation company’s representative note this on the bill of lading.

NOTE

Claims for shipping damages must be noted by the consignee at the point of destination and filed with the transportation company that delivers the shipment.

5

3—SPECIFICATIONS

3.1—ENGINESPECIFICATIONS

TYPE: Twin Cylinder, Air Cooled

ENGINE MODEL: Briggs & Stratton Vanguard

HORSEPOWER: 11.9 kw (16 hp)

COOLING: Ducted air flow

3.2—TRANSMISSION

TRACTIONDRIVE: Direct coupled variable displacement hydraulic pump with high torque wheelmotors.

OIL TANK: .............................

18.9 L (5 gallon) capacity

3.3—VEHICLESPECIFICATIONS

FUEL TANK: 18.9 L (5 gallon) capacity WHEELS AND TIRES:

Front: 20-10 x 8.00 Tubeless Turfmate

Rear: 18-8.50 x 8.00 Tubeless Turfmate TIRE PRESSURE: 10-12 PSI

FRAME: Welded steel construction MOWING SPEED: 0- 12 K/H (0 - 7.5 MPH) TRANSPORT SPEED: 12 K/H (7.5 MPH) REVERSE SPEED: 3 K/H (2 MPH) CONTROLS:

Foot operated traction pedal for forward and reverse.

Hand operated choke and throttle levers.

Foot operated hydraulic lift with auto start/stop feature.

Hand operated reel engagement lever.

Free-wheelingvalve.

3.4—BATTERY

TYPE: Group U1 Type GT

NOMINAL VOLTAGE: 12V

DIMENSIONS: L: 7-3/4”(19.68 cm) x W: 5-3/16” (13.17 cm) x H: 7-5/16”(18.5 cm)

3.5—MOWERSPECIFICATIONS

NUMBER AND SIZE: 3 – 25" Reels

REEL DIAMETER: 7" (17.8 cm) BEARINGS: Timken Tapered Roller

BLADES: Six Alloy Steel Blades

HEIGHT OF CUT: Adjustable: 1/2” to 2" (1.3 cm to

5.08 cm)

OVERALL CUTTING WIDTH: 70" (177.8 cm) HEIGHTADJUSTMENT:RollerScrewAdjustment

BEDKNIFE ADJUSTMENT: Screw adjustment of reel to bedknife.

REEL FLOATATION: Front and Rear Roller with Cutting

Unit Center-line Pivot.

3.6—WEIGHT&DIMENSIONS

OVERALL LENGTH: 86-3/8" (219.4 cm)

OVERALL HEIGHT: 44-3/4" (113.6 cm)

WHEEL BASE: 50-3/4" (128.9 cm)

WHEEL TREAD WIDTH: 45" (114.3 cm) (center of tires) OVERALL WHEEL WIDTH: 55" (139.7 cm)

OVERALL WIDTH: 75" (190.5 cm) WORKING WEIGHT: 1, 085 lbs. (492 kg)

3.7—LUBRICANTS

ENGINE OIL:

Use high-quality detergent oil API (American Petroleum Institute) service class SF. Select the viscosity based on the air temperature at the time of operation as shown in the table.

Recommended SAE Oil Viscosity Grades

HYDRAULIC SYSTEM OIL:

Use ISO GRADE 100 (SAE 30W) Hydraulic Oil

6

HY70OM-8/99

NATIONAL® HYDRO 70" TRIPLEX

3.8—DISPOSALNUMBERS

Petrol, Lead Free: .......................

54104

Engine oil: ...................................

54112

Fiberglass parts: .........................

57103

Tires: ...........................................

57502

Gear oil: ......................................

54112

Grease: .......................................

54202

Plastic tanks: ...............................

57127

3.10—TRANSFERS

07406

07257

07405

3.9—NOISEEMISSION&VIBRATION

Sound:

Operator Position, 88 dBA

 

Sound Power Level (LwA), 106 dBA

Vibration*:

Max. Vibration, 57.7 m/s2 RMS

 

Location, Left Hand

Operating Condition: Engine rpm-3200, Unit stationary

07403

NATIONAL MOWER CO.

700 RAYMOND AVE.

ST. PAUL, MINNESOTA 55114 USA 651-646-4079 FAX 651-646-2887

POWER RATING: 9.7 kW at: 3200 rpm

WEIGHT: 528 kg

07372

07256

07404

7

TRANSFERS,Continued

07408

 

 

 

 

07409

07407

 

 

3.11—TRANSFER DESCRIPTION

07406 Do not exceed 25 degree slope. Located on main chassis.

07403 Parking brake on/off. Located on main chassis.

07372 Manufacture’s identification and specifications. Located on main chassis.

07257 Mowers up/reels off. Located on main chassis.

07256 Mowers down/reels on. Located on main chassis.

07405 Sound level at operators position. Located on main chassis. 07404 Sound power level. Located on main chasis.

07408 Mow pedal operation and vehicle motion pedal operation. Located on main chassis. 07409 Main instrument panel, Three wheel drive unit. Located on main chassis.

07407 Main instrument panel, Two wheel drive unit. Located on main chassis.

8

HY70OM-8/99

4—ASSEMBLY INSTRUCTIONS

4.1—ASSEMBLY

The Hydro 70 is shipped in two separate crates, one for the tractor and one for the cutting units.

4.2—TRACTOR ASSEMBLY

1.Disassemble crating for the tractor carefully to prevent damage to components.

2.Remove the tape holding the keys in the steering shaft. Position the handlebar assembly over the shaft and key securing it with set screws provided it the handle bar.

NATIONAL® HYDRO 70" TRIPLEX

SEAT

SUPPORT

3.For removal of handle bar see Section 8.12.

4.Remove the tower cover. Refer to section 3.4 for battery specifications. Install the battery on the base inside the tower. Attach the red wire to the positive terminal of the battery and attach the black ground wire to the negative terminal of the battery. Replace and secure the tower cover.

HANDLEBAR

KEY

COVER

6.Tires should be checked and if necessary adjusted for proper inflation. Refer to Section 3.3.

7.Check the oil level in the oil tank. Refer to Section 8.10.

8.Check the oil level in the engine. Refer to 3.7 and 5.1.

4.3—ASSEMBLY OF REAR CUTTING UNIT TO TRACTOR

1.Disassemble crating for the cutting units carefully to prevent damage to components.

2.Position the rear cutting unit under the tractor. The rear cutting unit can be identified by the reel guard attached the rear of the cutting unit. Position the cutting unit with the reel pulley on the right side of the tractor.

NOTE

5. The seat base is temporally held together for shipment. Remove and discard the fastener securing the seat base to the spring plate. Position the seat slider, which is assembled to the seat, onto the seat base plate and secure with locknuts provided.

Attach the safety switch wires to the switch located under the seat. Wires can be connected to either terminal.

Belt tool kit Part# 070008 is available thru National Mower’s parts department. This tool will simplify the assembly of the cutting units.

3. Remove the tie wrap holding the pull arm and spring to the cutting unit. Assemble the pull arm to the tractor using the sleeve and fastener provided.

9

ASSEMBLY OF REAR CUTTING UNIT, Con't.

4.Remove the two top fasteners holding the pivot bracket to the cutting unit and loosen the bottom fastener so the bracket is free to rotate.

5.Align and assemble the spring and pull arm previously attached to the tractor to the pull arm shaft on the cutting unit. Place the belt on the cutting unit pulley.

With the pull arm assembled, rotate the pivot bracket into place using it as a lever arm to compress the spring and reattach with previously removed fasteners.

6.Assemble the pull rod on the left side of the cutting unit to the tractor using fasteners provided.

7.A counterbalance spring has been assembled to the tractor located under the steering tower. Remove the spring bushing from the cutting unit making note of its location. Insert the spring bushing into the spring loop, pull directly down on the spring and reinsert the fastener provided thru the bushing into the hole on the cutting unit.

8.Remove the tie wraps securing the lift chains and attach the chains to the lift arm under the tractor. One chain per side.

9.Remove the tie wrap attaching the cutting unit belts to the tractor. Position the cutting unit in front of the tractor with the pulleys to the inside. Remove the two top fasteners holding the pivot bracket to the cutting. Place the belt on the cutting unit pulley. Assemble the push arm to the pivot bracket using the washers and snap ring provided. Rotate pivot bracket into place using it as a lever arm to compress the spring and reattach with previously remove fasteners.

10.Attach counterbalance spring and chains to lift bar.

11.Connect link bar between cutting units with fasteners provided.

PUSHARM

LINK BAR

PIVOT

PULL

FRAME

 

BRACKET

ROD

PIVOT BRACKET

 

Belt tool, complete with instructions, (below) available through National Mowers Parts Department.

PUSH

PUSHARM,SPRING

PART # 070008

ARM

& SLEEVE

 

SHAFT

 

 

10

HY70OM-8/99

5—GENERAL INFORMATION

5.1—ENGINE

Your vehicle is powered by twin cylinder, 4 cycle Briggs & Stratton Vanguard engine which uses unleaded gasoline, 85 octane minimum. DO NOT MIX

OIL WITH GASOLINE! Engine speed is controlled by means of a throttle lever mounted on the left side of console panel.

A separate Engine Manual, prepared by the engine manufacturer is supplied. Study the manual carefully until you are familiar with the maintenance, operation, adjustment and repair of your equipment. Proper attention to the engine manufacturer’s directions will assure maximum service life of the engine and highest operating efficiency.

5.2—TRACTION DRIVE TRAIN

Power from the engine is transmitted to the variable displacement pump through a drive coupling.

The pump supplies hydraulic fluid to wheel motors. The wheel motors provide the differential action required in turns.

NATIONAL® HYDRO 70" TRIPLEX

b.Key should be removed when tractor is not in use to prevent unauthorized operation.

c.Refer to section 4.2 in the Hydro 70 Operator’s Manual for complete starting information.

5.5—HOUR METER

The hour meter indicates the number of hours the tractor has been operated. It can be used to keep track of maintenance intervals and the amount of time required to perform various tasks. The hour meter operates whenever the ignition key is in the “ON” position.

5.6—AMMETER

The ammeter indicates the condition of the charging circuit. If the ammeter indicates a negative reading refer to the Briggs and Stratton engine manual.

5.3—REELDRIVE

Power to the reels is transmitted from the engine to a jackshaft mounted under the engine through a spring loaded belt drive. Three separate belts trans-mit the power from the jackshaft to the mowers.

5.4 IGNITION SWITCH

The reel control lever must be in the disengage position and the traction control pedal is in the neutral position before starting engine. Insert key in switch, turn clockwise as far as it will go to start engine, then release.

a. Do not hold key in “ON” position more than

30 seconds at a time.

5.7—REEL CONTROL

The reel control lever must be in the disengaged or back position to start the engine. Placing lever in engaged position will allow reels to run when mowers are lowered.

Never operate the mowers when they are not cutting grass as excessive friction and heat will develop between the bedknife and reel, and damage the cutting edge.

11

5.8—CHOKE

When starting a cold engine, pull the choke control out to close the choke plate and allow a richer fuel mixture to enter the engine. After the engine starts, push the choke control about half way in to keep the partially closed. Push the choke control all the way in to open the choke plate for normal operation after the choke plate engine is properly warmed. A warm engine usually requires less choke to start.

The valve is located under the left shield on the front side of the vehicle. With the engine “OFF”, turn knob to open valve and permit free-wheeling. Freewheeling valve must be closed during normal operation or tractive effort will be severely reduced.

5.9—THROTTLE LEVER

Push forward to increase engine speed, pull back to decrease.

5.13—DROP/LIFT NEEDLE VALVE

A needle valve is located under the left shield on the front side of the vehicle. By turning the needle valve knob, the speed of drop and raising of the cutting units can be adjusted as desired.

5.10—TRACTION PEDAL

The traction pedal operates the forward and reverse direction and speed of the machine. By pushing the toe of the pedal down, the forward speed is increased. By pushing the heel of the pedal down the reverse speed is increased. When the traction pedal is released the machine will slow down and stop.

Familiarize yourself with the instrument panel and the controls. Study the instructions and learn to use the controls correctly. Keep hands and feet away from controls unless you intend to use them.

5.11—MOW AND LIFT TREADLE

Depress and hold the down pedal with left foot to lower mowers. Reels will rotate if reel control lever is in “ENGAGED” position. Depress and hold the up pedal to raise mowers. Reels will stop if control lever is in

“ENGAGED” position when mowers are raised.

NOTE

When operating the mow or lift pedal, keep the pedal depressed until the mowers have been completely lowered or raised, and then release the pedal.

5.12—FREE-WHEELINGVALVE

To permit moving the Hydro 70 without starting the engine, a freewheeling device or tow valve has been provided.

3.13 INTERLOCK SWITCHES

There are four interlock switches on your Hydro

70. They are a safety precaution which will allow you to start your mower only when the traction pedal is in neutral, the reel control lever is in the disengaged position and operator is seated on the tractor. If you are able to start your mower with these levers in any other position, adjustment of the switches is required.

1.The neutral start switches are located under the traction control pedal.

2.The reel control lever switch is located on the side of the console and is activated by the reel lever.

3.The seat switch is located under the seat and is activated by the weight of the operator.

12

HY70OM-8/99

6—OPERATION

See Section 4.0 in the National Mower Hydro 70

Operators Manual for unit operation.

7—ADJUSTMENTS

7.1—ADJUSTMENTS

Read each instruction completely and make sure you understand it before making any adjustment. Follow all the safety precautions.

To avoid possible serious bodily injury, before making any adjustments or performing maintenance, place all tractor controls in Neutral, engage parking brake, fully lower cutting units to the ground, turn ignition switch “Off” and remove key.

NATIONAL® HYDRO 70" TRIPLEX

TRACTION PEDAL

TRACTION PEDAL

SAFETY SWITCHES

THREADED ROD &

ROD END

PUMP CONTROL

BEARING

7.2—TRACTION PEDAL

ADJUSTMENT

The Traction pedal is equipped with two safety switches and a neutral centering device. The switches prevent the engine from starting when the pedal is positioned in reverse or forward. The centering device locates neutral positioning of the pump.

Prior to adjusting for creep, elevate the wheels off the ground and support the vehicle securely. Any adjustments should be done while the hydraulic oil is warm.

To adjust the creep of the drive wheels loosen the fastener attaching the ball bearing to the control arm and move the bearing within the slot to achieve neutral.

Once the traction pedal has been adjusted, the switches may have to be re-adjusted by moving the switches in the range of the slots provided in the switch bracket. Adjust switches so that unit cannot be started unless pedal is in the neutral position.

7.3—REEL CONTROL CLUTCH ADJUSTMENT

The reel control clutch idler is preset at the factory. However, if adjustment is necessary, the position of the idler can be adjusted with the clevis on the clutch rod.

Loosen the jam nut that locks the clevis to the clutch rod and turn the clevis further onto the rod until proper tension is achieved, and re-tighten nut against clevis.

If clevis bottoms out on the threaded rod replace the belts.

CLEVIS

CLUTCH ROD

CLUTCHIDLER LIFT STRAP

13

REEL CONTROL CLUTCH

ADJUSTMENT, Continued

If clutch idler is restricted from its proper function, (engaging and disengaging reel belt drive), follow these steps. Refer to figure on the previous page.

1.Make sure clutch rod is free from any restriction by moving lever arm back and forth.

2.Loosen mounting bolts for the clutch idler. If the mounting bolts are torqued too tight, it restricts idler movement.

3.Loosen the pivot bolt between the idler arm and lift strap. Any restriction at this point will cause restriction with the idler arm.

7.4— SEAT SWITCH ADJUSTMENT

The HYDRO 70 has a safety switch mounted directly to the seat bottom. The switch requires no adjustment.

If wires should become disconnected from the seat switch it prohibits other safety features from working properly.

To avoid possible serious bodily injury, before performing any adjustments, maintenance, or lubrication, place all controls in “Neutral”, lower the mowers to the ground, engage parking brake, turn ignition switch off and remove key.

7.5—HEIGHT OF CUT ADJUSTMENT

The height of cut is variable and adjusted by moving the front and rear roller brackets to the desired height.

It is important to get all rollers adjusted to the same height, keeping the bed knife parallel to the ground, so that there will be uniform cutting on the entire width of the mower. Do not adjust rollers by sight.

After loosening adjusting nuts on each side of the reel assembly, place a gauge plate under the bedknife and roller measuring the distance between bedknife cutting edge and the rollers. Adjust front and rear rollers equally and insure that the bottom of the bedknife is parallel with the ground. After height of cut setting is determined, re-tighten roller adjustment nuts.

NOTE

A height of cut tool, Part #070009 (shown below), complete with instructions, is available through the National Mower

Parts Department.

ROLLER ADJUSTERS

BED BAR

BED

KNIFE

BAR

ROUND HEAD

 

HEXHEAD

SCREW

WINGNUT

CAPSCREW

INSTRUCTIONS:

1.Preparation of bar—Position round head capscrew to desired height of cut. Measure from flat surface of bar to the underside of round head screw. Lock round head screw in position with wing nut.

Position hex head capscrew 1/8 less than desired height of cut. Measure from flat surface of bar to the top of the hex head capscrew. Lock hex head capscrew in position with wing nut.

2.Setting height of cut—Hook round head screw on top edge of bedknife, and rest hex head capscrew against bedbar.

Adjust front and rear roller adjusters so that the rollers contact bar. Check roller placement for the full length of the cutting unit by moving the bar side to side while still located on the bedknife/bedbar to achieve consistent height of cut the full width of the cutting unit. Lock roller adjusters in place.

14

HY70OM-8/99

7.6— REEL TO BEDKNIFE

ADJUSTMENT

The reel is adjusted to a fixed position bedknife.

This makes a more rugged and stable frame retaining adjustmentlonger.

To adjust the reel to bedknife contact, turn the hex adjuster on each side of the reel down. Proceed slowly and do not over adjust - about 1/8th of a turn on each side. Do not over tighten. A too tight reel will wear much faster. The reel should “wipe” or lightly touch the bedknife. By using paper strips held between reel and bedknife, check to see that blades are cutting the paper all the way across.

Use heavy gloves and be careful— blades are sharp!

7.7—REEL END PLAY ADJUSTMENT

As the reel is used, normal wear of the reel bearings will cause end play. This condition could cause uneven wear to moving parts and uneven cutting of turf.

Test for end play periodically by trying to move the reel from side to side in the frame. If there is any movement, adjust by loosening the locknut on the adjustment body, which is located on the inside right end of the reels and turn adjustment bolt in a half turn or less. Do not overtighten as it would cause excessive bearing wear. Test again for end play, if reel is rotating freely and end play can not be detected, retighten the locking nut on adjustment bolt.

LOCKNUT & SCREW

NATIONAL® HYDRO 70" TRIPLEX

7.8— BACKLAPPING PROCEDURE

Back lapping is a very important step in maintaining sharp reel blades on the rear and wing mowers.

Many types of compounds are available for lapping. However, we recommend a good premixed water soluble compound such as Pinhigh. Prices, grit ranges and ordering information are available by calling a toll free phone number 1-800-422-4748. Pre-mixed compound saves the time required to mix, eliminates the waste of abrasive, rinses off easily with water and is available in all grit ranges from coarse to extra fine.

This procedure should be performed when the reel blades and bed knife become slightly rounded and the grass is not cut cleanly with only a slight bedknife adjustment. After grinding the bedknife and reels, backlapping should be done to establish a perfect match between the bedknife and reel blades.

1.Clean cutting units of any foreign debris and disengage reel clutch.

2.Make sure to adjust the bedknife to the reel so that the bedknife is level with the reel and light contact is maintained.

3.Reels must be run in a reverse direction to be lapped. Remove exterior guards as needed. Attach a back lapping machine (not supplied by National

Mower) to one of the outside reel stub shafts of the front two cutting units, following the instructions furnished by the backlapping machine manufacturer.

NOTE

Some back lapping machines may not rotate all three cutting units simultaneously. If this occurs back the reel adjustment off or disconnect the remaining two cutting units and concentrate on one cutting unit at a time.

4.With reels running, and concentrating on one reel, apply the lapping compound using a 2" or 3" wide brush. Apply the compound evenly to the mowing blades. Adjustment of the reel to bedknife may be required, relap as necessary.

Be extremely careful not to let the brush, your fingers or your clothing get caught in the reels. Use approved safety glasses to protect eyes from flying particles and abrasives.

15

BACKLAPPINGPROCEDURE, Continued

5.Stop the reel and examine both bed knife and reel blades to see that the cutting edges are uniformly sharp. If not, gradually tighten hex adjuster and repeat Step 4 on previous page until the proper sharpness results.

6.Rinse off the compound thoroughly with water to remove all abrasive. Check for sharpness and readjust the bed knife if necessary.

7.Check reel adjustment on each mower and adjust if necessary, so that they will cut paper cleanly across the full length of the bed knife when paper is held

90# to the bedknife and pinched when held horizontally.

7.9—GRINDINGPROCEDURE

BACK GRIND IN THE

DIRECTION

OF THE ARROW AT 25O

25O

Be extremely careful not to let brush, your fingers or your clothing get caught in the reels. Use approved safety glasses to protect tour eyes from flying particles and abrasives.

Reels must be ground at 25° in the direction shown by the arrow. Back grind until reel blades are free from roundness, dents and nicks. Spin grind to remove all burrs. All blades

must be on the same diameter.

For maximum cutting efficiency, grind bed knife top and front edges at 5° as shown.

GRIND BED KNIFE

AT ANGLES SHOWN

5O

5O

Note centerline

POSITION OF REEL

TO THE BLADE

16

HY70OM-8/99

+ 35 hidden pages