RESIDENTIAL PRODUCTS
SINGLE STAGE SNOW
ENGINE SERVICE MANUAL
LC168F / LC168FD (163cc)
About this Manual
This service manual was written expressly for Toro service technicians. The Toro Company
has made every effort to make the information in this manual complete and correct. Basic shop
safety knowledge and mechanical/electrical skills are assumed. The Table of Contents lists the
systems and the related topics covered in this manual. An electronic version of this service
manual is available on the Toro Dealer Portal. We are hopeful that you will find this manual a
valuable addition to your service shop. If you have any questions or comments regarding this
manual, please contact us at the following address:
The Toro Company
Residential and Landscape Contractor Service Training Department
8111 Lyndale Avenue South
Bloomington, MN 55420
Chapter 1 – General Service Information
1
Chapter 2 - Engine Service / Maintenance
2
Chapter 3 - Engine Disassembly and Service
3
Chapter 4 - Electrical
4
NOTES:
0
1
Chapter 1 – General Service Information
Safety 2
Service Rules 3
Engine Model / Serial Number Location 3
Engine Fastener Torque Specification 4
General Specifications 5
Engine Specifications 5
Troubleshooting 6
1
Safety
Safety Information
This symbol means WARNING or PERSONAL SAFETY INSTRUCTION – read the instruction because it has
to do with your safety. Failure to comply with the instruction may result in personal injury or even death.
This manual is intended as a service and repair manual only. The safety instructions provided herein are for
troubleshooting, service, and repair of the Toro engine. The Toro operator’s manual contains safety
information and operating tips for safe operating practices.
Avoid Unexpected Engine Start - Turn off engine and disconnect the spark plug before servicing engine.
Avoid Lacerations and Amputations - Stay clear of all moving parts while the engine is running.
Avoid Burns - Do not touch the engine, muffler, or other components which may increase in temperature
during operation, while the unit is running or shortly after it has been running.
Avoid Fires and Explosions - Avoid spilling fuel and never smoke while working with any type of fuel or
lubricant. Wipe up any spilled fuel or oil immediately. Never remove the fuel cap or add fuel when the engine
is running. Always use approved, labeled containers for storing or transporting fuel and lubricants.
Avoid Asphyxiation - Never operate an engine in a confined area without proper ventilation.
Avoid Injury From Batteries - Battery acid is poisonous and can cause burns. Avoid contact with skin, eyes,
and clothing. Battery gases can explode. Keep cigarettes, sparks, and flames away from the battery.
Avoid Injury Due To Inferior Parts - Use only original equipment parts to ensure that important safety
criteria are met.
Avoid Injury To Bystanders - Always clear the area of bystanders before starting or testing power
equipment.
Avoid Injury Due To Projectiles - Always clear the area of sticks, rocks, or any other debris that could be
picked up and thrown by the power equipment.
Avoid Modifications - Never alter or modify any part unless it is a factory approved procedure.
2
1. Only use genuine Toro parts and lubrication products.
2. Always install new gaskets, O-rings and seals when assembling engine.
3. Always torque fasteners to specification and in sequence.
4. Always lubricate friction components with clean engine oil or engine assembly lube
when assembling engine.
1
Engine Model and
Serial Numbers
Engine Model
Serial Number
Service Rules
Engine Model / Serial Number Location
2010-2011 - The engine model and serial number are stamped into the crankcase near the electric starter
mounting position on the side of the engine towards the front of machine (shown below).
2012 - The engine model and serial number are stamped into the crankcase near the rear of the machine.
XXX-XXXX XXXXXXXXXXX
3
Item
Torque
Specification
Oil Drain Plug
17 ft-lbs (23 Nm)
Connecting Rod Bolts
8.5 ft-lbs (12 Nm)
Crankcase & Cover Bolts
17.5 ft-lbs (24 Nm)
Valve Lash Lock Nut
11 ft-lbs (15 Nm)
Rocker Arm Studs
22 ft-lbs (30 Nm)
Spark Plug
22 ft-lbs (30 Nm)
Valve Cover Bolts
7 ft-lbs (10 Nm)
Starter Bolts
7 ft-lbs (10 Nm)
Recoil Mounting Bolts
7 ft-lbs (10 Nm)
Cylinder Head Bolt
25 ft-lbs (34 Nm)
Heater Box Nuts
7 ft-lbs (10 Nm)
Flywheel Nut
62.5 ft-lbs (85 Nm)
Ignition Coil Bolts
7 ft-lbs (10 Nm)
Throttle Control Bolts
7 ft-lbs (10 Nm)
Governor Arm Nut
7 ft-lbs (10 Nm)
Muffler / Exhaust to Cylinder Nuts
22 ft-lbs (30 Nm)
Muffler Mounting Plate Bolts
7 ft-lbs (10 Nm)
Standard Torque Values
M5 Bolt / Nut
4.5 ft-lbs (6 Nm)
M6 Bolt / Nut
7.5 ft-lbs (10 Nm)
M8 Bolt / Nut
19 ft-lbs (26 Nm)
M10 Bolt / Nut
28 ft-lbs (38 Nm)
M12 Bolt / Nut
41 ft-lbs (55 Nm)
Engine Fastener Torque Specifications
4
MODEL
LC168F-1 (Recoil Start)
LC168FD-1 (Electric Start)
Engine Type
OHV Single Cylinder, Four Stroke, Forced Air Cooling
Displacement (cc)
163
Bore x Stroke (mm)
68 x 45
Compression Ratio
8.5:1
Engine Operating RPM
3550 - 3850 RPM
Oil Capacity
20 oz. (0.6 l)
Fuel Type
Unleaded Gasoline, 87 Octane
Ignition System
T.C.I Transistorized Magneto
Lubrication System
Splash
Cylinder
Aluminum with Cast Iron Bore
Spark Plug
Gap
0.0275 - 0.0314” (0.7-0.8 mm)
Valve
Clearance
Intake Cold
0.0059” (0.15 mm)
Exhaust Cold
0.0078” (0.20 mm)
Ignition Coil
Resistance (primary)
1-1.6Ω
Resistance (secondary)
15.5K Ω ±15%
Gap to Flywheel
0.011- 0.019” (.3-.5 mm)
1
General Specifications
Engine Specifications
NOTE: The only internal parts available for this engine are gaskets and seals.
5
Troubleshooting
Hard Starting / Poor Running
- Incorrect Fuel (Level, Age, Octane, Ethanol Content)
- Fuel System Contamination and / or debris in Carburetor
- Incorrect Oil Level
- Spark Plug (Incorrect Gap, Fouled, Loose or Faulty)
- Air Intake System Leaks
- Ignition Coil to Flywheel Gap Incorrect
- Weak / No Spark
- Choke / Linkage
- Operating RPM Incorrect
- Governor Adjustment Incorrect
- Engine Valve Clearance out of Specification
- Low Compression or Excessive Leakdown
Overheating
- Incorrect Oil Level
- Cylinder Head Gasket Leak
- Debris Build-Up Restricting Air Flow
6
2
Chapter 2 - Engine Service / Maintenance
Engine Oil Change Procedure 8
Spark Plug Service 9
Valve Clearance Inspection and Adjustment 10
Engine Governor – Zero Point Setting 11
Engine RPM Adjustment 11
Fuel Filter Replacement 12
7
Engine Oil Change Procedure
1. Run engine to warm engine oil.
2. Remove the ignition key.
NOTE: Ensure fuel system contains no fuel to prevent leakage when engine is tipped.
3. Position oil drain pan under oil drain plug.
4. Remove the oil fill / check cap.
5. Remove the oil drain plug. If necessary, replace drain plug gasket.
6. Tip engine slightly backwards (if necessary) to completely drain the engine oil.
7. Install the oil drain plug - torque to 17 ft-lbs (23 Nm).
8. Add oil through the oil check / fill hole. Wipe the dipstick clean and insert it into the dipstick hole.
NOTE: DO NOT fully install / screw in the dipstick to check the oil.
9. Remove the dipstick and check the oil level – Add oil if needed until the proper oil level is reached.
NOTE: DO NOT overfill the engine oil
10. Fully install and tighten the dipstick.
11. Properly dispose of the used engine oil.
Engine Oil Capacity:
20 oz. (0.6 l)
Engine Oil Type:
API classification of SF,SG, SH, SJ, SL, or higher.
8
0.0275 - 0.0314”
(0.7-0.8 mm)
2
Spark Plug
Spark Plug Service
NOTE: Spark plugs of the wrong size or incorrect heat range can cause severe engine damage.
NOTE: The shrouding, discharge chute and handle may need to be removed to access the spark plug.
High Voltage Ignition Systems can be Dangerous - Use Caution when Servicing Ignition Systems
1. Disconnect the spark plug boot and thoroughly clean the spark plug area.
2. Remove the spark plug from the engine.
3. Inspect the spark plug for excessively worn electrodes, chips or cracks in the insulator, or excessive
deposits.
4. Measure the electrode gap and adjust if necessary. Spark Plug Gap: 0.0275 - 0.0314” (0.7-0.8 mm)
5. Install spark plug and torque to specification - 22 ft-lbs (30 Nm).
6. Fully install the spark plug boot on the plug.
NOTE: Be sure breather tube is routed above the spark plug wire.
Image for reference only
9
Feeler Gauge
Rocker Arm
Pivot Lock Nut
Rocker Arm Pivot
Valve Clearance Inspection and Adjustment
NOTE: Valve clearance inspection and adjustment must be done with the engine cold.
1. Rotate engine to TDC (top-dead-center) of the compression stroke.
2. Remove the valve cover. Be sure both valves are completely closed and the decompression arm is not
holding the valve open.
3. Measure the clearance between the rotator and the valve stem with a feeler gauge.
NOTE: Be sure feeler gauge blade is not opening the valve while measuring valve clearance
Intake: 0.0059” (0.15 mm)
Exhaust: 0.0078” (0.20 mm)
4. To adjust valve clearance:
- Hold the rocker arm pivot and loosen the pivot lock nut.
- Turn the rocker arm pivot to obtain the specified clearance.
- Hold the rocker arm pivot and tighten the pivot lock nut to specification - 11 ft-lbs (15 Nm).
5. Recheck the clearance and readjust if necessary.
6. Inspect the valve cover gasket and replace if necessary. Install the cylinder head cover and torque
fasteners to specification - 7.5 ft-lbs (10 Nm).
10
D
2
B
A
C
Engine Governor – Zero Point Setting
1. Loosen but do not remove the governor pinch bolt nut (A).
2. Move the governor arm (B) towards the carburetor to fully open the throttle valve. Firmly hold the
governor arm in this position.
3. Rotate the governor arm shaft (C) fully clockwise and secure it in this position with a pair of pliers.
4. Tighten the governor arm pinch bolt (A) and nut to specification - 7.5 ft-lbs (10 Nm).
5. Verify that the governor arm and throttle valve move freely.
6. Start and warm engine.
7. Verify the engine operating RPM is set between 3550 - 3850 RPM.
Engine RPM Adjustment
1. Properly set the governor zero point as shown in this
manual.
2. Start and warm engine.
3. Attached an appropriate tachometer to the engine.
4. Adjust engine RPM by turning the High Speed Setting
Screw (D) located above the carburetor asm.
Engine Operating RPM - 3550 - 3850 RPM
11
A
Fuel Filter and Hose Replacement
- Fuel is Extremely Flammable - Use Extreme Caution When Servicing Fuel System
1. Drain the fuel tank into an approved container.
NOTE: Ensure fuel system contains no fuel to prevent leakage when the fuel filter is replaced.
2. Release the fuel filter / fuel hose clamps (A) and slide them away from the fittings.
3. Remove the fuel filter / hose asm. from the engine.
4. Properly install new fuel filter / hose asm. and hose
clamps (A).
5. Re-fill tank with fresh fuel.
6. Verify hose routing and check for leaks.
7. Properly dispose of any unused fuel.
12
3
Chapter 3 - Engine Disassembly and Service
Engine Service – Upper End 14-23
Muffler / Heat Shield Exploded View 14
Heater Box Exploded View 15
Carburetor Mounting 16
Carburetor Exploded View 17
Recoil Asm. Exploded View 18
Starter / Flywheel / Coil Exploded View 19
Cylinder Head Exploded View and Service Information 20
Cylinder Head / Valves Exploded View and Service Information 21
Cylinder Head Specifications 22
Valve Seat Reconditioning 23
Engine Service – Lower End 24-27
Crankcase Exploded View and Information 24
Governor Exploded View 25
Piston / Connecting Rod Exploded View and Information 26
Valve Timing 27
NOTE: The only internal parts available for this engine are gaskets and seals.
13
Muffler / Exhaust Pipe
22 ft-lbs (30Nm)
Gasket
Muffler Mount Bracket
7 ft-lbs (10Nm)
Engine Service – Upper End
Muffler / Heat Shield Exploded View
14
Wing Nut
7 ft-lbs (10Nm)
Gasket
Note Orientation for Assembly
Heater Box
Base
Cover
Spacer and Washer
3
Up
Heater Box Exploded View
15
Gasket
Note Orientation for Assembly
Spacer
Gasket
7 ft-lbs (10Nm)
Primer Hose
Fuel Hose
Cylinder Head
Carburetor Mounting
16
O-ring
Exchange
Jet
Choke Lever
Choke Plate
Throttle Shaft
Stop Screw
Main Jet
Nozzle
Needle and Asm.
Float
Gasket
Pin
Float Bowl
Drain Screw
7 ft-lbs (10 Nm)
Gasket
3
Carburetor Exploded View
.
17
Shroud and Recoil Asm.
7 ft-lbs (10 Nm)
Set Screw
Guide
Ratchet
Spring
Clip
Spring
Recoil Housing
Wheel
Recoil Asm. Exploded View
18
Starter Asm.
(Optional)
Blower Shroud
Electric Start
Blower Shroud
Recoil Start
Side Plate
7 ft-lbs (10 Nm)
7 ft-lbs (10 Nm)
Ignition Coil Asm.
Flywheel Nut
62.5 ft-lbs (85 Nm)
Cup
Fan
Flywheel
3
Starter / Flywheel / Coil Exploded View
Image for Reference Only
Starter Removal
1. Remove recoil and shroud asm.
2. Remove flywheel with an appropriate puller.
3. Remove the fasteners securing the starter motor to the engine and remove starter asm.
19
Spark Plug
Cylinder Head Bolts
25 ft-lbs (34 Nm)
7 ft-lbs (10 Nm)
Valve Cover
Gasket
Cylinder Head
7 ft-lbs (10 Nm)
Shroud
Gasket
Cylinder Head Bolt Torque Sequence:
1. Initially Torque the (4) Cylinder Head Bolts in a Crisscross Pattern to 10 ft-lbs (14 Nm).
2. Evenly Torque the (4) Cylinder Head Bolts in a Crisscross Pattern to 25 ft-lbs (34 Nm).
Dowl
NOTE: The only internal parts available for this engine are gaskets and seals.
Cylinder Head Exploded View and Service Information
20
Exhaust Valve
Intake Valve
Push Rod
Valve Spring
Retainer
Rotator
Valve Lash Lock Nut
11 ft-lbs (15 Nm)
Rocker
Arm
Pivot
Stud
22 ft-lbs (30 Nm)
3
NOTE: The only internal parts available for this engine are gaskets and seals.
Cylinder Head / Valves Exploded View and Service Information
21
Standard
Service limit
0.03149” (0.8mm)
0.07874” (2.0mm)
Service Limit
0.00393” (0.10 mm)
STRAIGHT EDGE
FEELER GAUGE
Valve Seat Width Inspection
Remove carbon deposits from the combustion chamber. Inspect the valve seats for pitting or other damage.
Cylinder Head Warp Inspection
- Remove carbon deposits from the combustion
chamber.
- Clean off any gasket material from the cylinder head surface.
- Check the spark plug hole and valve areas for cracks.
- Check the cylinder head for warpage with a straight
edge and a feeler gauge as shown.
NOTE: If this measurement is out of specification, complete engine replacement is required.
The only internal parts available for this engine are gaskets and seals.
22
Standard
Service Limit
0.03149” (0.8mm)
0.07874” (2.0mm)
CONTACT TOO LOW
CONTACT TOO HIGH
3
Valve Seat Reconditioning
1. Thoroughly clean the combustion chamber and valve seats to remove carbon deposits.
2. Apply a light coat of Prussian Blue or erasable felt-tipped marker ink to the valve faces.
3. Properly install valves, springs and keepers. Manually open the valves, then and snap them closed
against their seats several times. Be sure the valves do not rotate on the seat. Remove the valve
assemblies. The transferred marking compound will show any area of the seat that is not concentric.
4. Use a 45°cutter to remove enough material to produce a smooth and concentric seat. Follow the valve
seat cutter manufacture’s instructions. Turn the cutter clockwise, never counterclockwise. Continue to
turn the cutter as you lift it from the valve seat.
5. Use a 30°~32° and 60° cutter to narrow and adjust the valve seat so that it contacts the middle of the
valve face. The 30°~32° cutter removes material from the top edge. The 60° cutter removes material from
the bottom edge. Be sure that the width of the finished valve seat is within specification.
6. Lap valves in accordance with valve lapping kit instructions.
7. Clean valve and seat of all lapping compound.
Valve Seat Width
23
17.5 ft-lbs (24 Nm)
Seal
Bearing
Gasket
Crankshaft
Key
Bearing
Governor
Governor
Shaft
Crankcase Cover
Triangular Mark to Face Down
Piston Asm.
Camshaft
8.5 ft-lbs
(12 Nm)
Seal
NOTE: The only internal parts available for this engine are gaskets and seals.
Engine Service – Lower End
Crankcase Exploded View and Service Information
24
Shaft
Washer
Governor Gear
Weight
Clip
Slider
Governor
Shaft
Clip
Washer
Pin
3
NOTE: The only internal parts available for this engine are gaskets and seals.
Governor Exploded View
25
Point Down to
Match Piston Arrow
Top Ring / Gap
Second Ring / Gap
Oil Rings
Stagger Scraper Rings
150°～ 210° from the Oil Ring
Install Piston Ring
Markings “UP”
Triangular Mark to Face “DOWN”
Towards Push Rods
Oil Splash Spoon
Connecting Rod
Piston Pin Clip
Piston Rotation Arrow
Piston Pin
Clip Gap
Piston Cut-out
8.5 ft-lbs
(12 Nm)
Piston / Connecting Rod Exploded View and Service Information
26
Crankshaft
Camshaft
Timing Marks
3
Valve Timing
27
NOTES:
28
4
Chapter 4 – Electrical System Information
Ignition Coil Gap Adjustment 31
Ignition Coil Resistance Inspection 32
Spark Testing 32
29
Ignition Coil Gap
0.011- 0.019”
(.3-.5 mm)
Ignition Coil
Flywheel
0.011 – 0.019
(.3-.5mm)
Ignition Coil Gap Adjustment
High Voltage Ignition Systems can be Dangerous - Use Caution when Servicing Ignition Systems
1. Install the ignition coil and lightly tighten the ignition coil mounting bolts.
2. Rotate engine so ignition coil is aligned with the magnet portion of the flywheel.
3. Insert the feeler gauge between the flywheel and coil.
4. Adjust the ignition coil gap at both side of the coil.
5. Torque the ignition coil mounting fasteners to specification - 7 ft-lbs (10 Nm)
30
A - Primary Coil Resistance
1.0-1.6 Ω
B - Secondary Coil Resistance
15.5 KΩ +/- 15%
A
B
4
Image for Reference Only
Ignition Coil Resistance Inspection
Primary Coil
Place Ohm meter leads between the harness connection
lead and the exposed metal coil leg.
Secondary Coil
Place Ohm meter leads between exposed metal coil leg
and the spark plug terminal connection.
Spark Testing
- Fuel is Extremely Flammable - Use Extreme Caution When Servicing the Fuel System
- High Voltage Ignition Systems can be Dangerous - Use Caution when Servicing Ignition Systems
1. Remove spark plug boot from the spark plug.
2. Remove the spark plug from the engine.
3. Connect the negative (-) electrode of the spark plug (threaded area) to ground (cylinder head cover).
4. Crank the engine and view the electrode gap. Spark should be present when engine is turning over.
5. Reinstall the spark plug and torque to specification - 22 ft-lbs (30 Nm).
6. Properly install the spark plug boot.
31
RESIDENTIAL PRODUCTS
Form Number: 492-9230
32
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