KAWASAKI FH641V (01) PDF Document

To protect the environment, your KAWASAKI FH641V engine has incorporated crankcase emission and exhaust emission control systems (EM) in compliance with applicable regulations. These systems include:

1. Crankcase Emission Control System: A sealed-type crankcase emission control system is used to eliminate blow-by gases. The blow-by gases are led to the breather chamber through the crankcase, then to the air cleaner. Oil is separated from the gases in the breather chamber and returned to the bottom of the crankcase.

2. Exhaust Emission Control System: This system consists of a carburetor and an ignition system with optimum ignition timing characteristics. The carburetor is calibrated to provide lean air/fuel mixture characteristics and optimum fuel economy with a suitable air cleaner and exhaust system.

Federal law and California State law prohibit the removal or rendering inoperative of any device or element of design incorporated into the engine for emission control purposes. Among those acts presumed to constitute tampering are the acts listed below:

Do not tamper with the original emission related parts, including:

• Carburetor and internal parts

• Spark plugs

• Magneto or electronic ignition system

• Fuel filter element

• Air cleaner elements

• Crankcase

• Cylinder heads

• Breather chamber and internal parts

• Intake pipe and tube

The manual for the KAWASAKI FH641V uses several symbols to help you distinguish different types of information:

WARNING: This symbol identifies special instructions or procedures which, if not correctly followed, could result in personal injury, or loss of life.

CAUTION: This symbol identifies special instructions or procedures which, if not strictly observed, could result in damage to or destruction of equipment.

NOTE: This symbol indicates points of particular interest for more efficient and convenient operation.

Before beginning service on your KAWASAKI FH641V, please note the following precautions:

(1) Dirt: Before removal and disassembly, clean the engine. Any dirt entering the engine will work as an abrasive and shorten its life.

(2) Battery Ground: Remove the ground (—) lead from the battery before performing any disassembly to prevent accidental turnover, sparks, and damage to electrical parts.

(3) Tightening Sequence: When installing a part with several bolts, nuts, or screws, start them all and tighten them to a snug fit. Then tighten them evenly in a staggered sequence to avoid distortion.

(4) Torque: Use a good quality, reliable torque wrench to tighten fasteners to the specified values.

(5) Force: Use common sense. If a part is difficult to remove or install, stop and examine the cause. Use a wooden or plastic-faced mallet for tapping when necessary.

(6) Edges: Watch for sharp edges. Protect your hands with gloves or a thick cloth.

(7) High-Flash Point Solvent: Use a high-flash point solvent to reduce fire danger.

(8) Gasket, O-Ring: Do not reuse gaskets or O-rings once they have been in service.

(9) Liquid Gasket, Locking Agent: Follow manufacturer’s directions. Apply sparingly to avoid blocking oil passages.

(10) Press: A part installed using a press should first be coated with oil on its outer or inner circumference.

(11) Ball Bearing: When installing a ball bearing, push the race that is affected by friction with a suitable driver.

(12) Oil Seal and Grease Seal: Replace any removed seals with new ones. Press them in with the manufacturer’s marks facing out.

(13) Seal Guide: Before a shaft passes through a seal, apply a little oil or grease to the seal lips.

(14) Circlip, Retaining Ring: Replace any removed circlips and retaining rings with new ones.

(15) Cotter Pin: Replace any removed cotter pins with new ones.

(16) Lubrication: During assembly, apply oil or grease to any rubbing surface that has lost its lubricative film.

(17) Electrical Wires: Wires are either single-color or two-color. They must be connected to wires of the same color.

(18) Replacement Parts: When instructed, replace parts with new ones every time they are removed.

Specifications are subject to change without notice.

To ensure satisfactory operation, your KAWASAKI FH641V engine requires normal maintenance at regular intervals. The following chart shows the periodic inspection and maintenance items and their suitable intervals. A bullet mark (•) indicates that the item should be performed at that interval.

(1): Service more frequently under dusty conditions.

★: These items must be performed with the proper tools. See your authorized Kawasaki Engine Dealer for service, unless you have the proper equipment and mechanical proficiency.

The following tables list the tightening torque for major fasteners on the KAWASAKI FH641V. Letters in the “Remarks” column have the following meanings:

• L: Apply a non-permanent locking agent to the threads.

• O: Apply an oil to the threads, seated surface, or washer.

• S: Tighten the fasteners following the specified sequence.

• SS: Apply silicone sealant.

FH601V, FH641V, FH680V, FH721V

Basic Torque for General Fasteners (for bolts and nuts which do not require a specific torque value)

Governor Arm Removal

1. Remove the Control Panel Assembly.

2. Loosen the clamp nut [A] and take off the governor arm [B].

3. Unhook the throttle link rod spring [C] end loop and clear the throttle link rod lower end [D].

Governor Arm Installation

1. Install the governor arm [A] onto the governor shaft [B] temporarily.

2. Be sure the link spring [C] around the throttle link rod [D] is in place and that it pulls the governor arm and throttle lever [E] toward each other.

3. Loosen the clamp nut [F] on the governor arm enough to move the governor shaft.

4. Turn the top end of the governor arm counterclockwise to fully open the carburetor [G] throttle valve and hold it there.

5. Turn the governor shaft counterclockwise, fully turning the shaft to the end of its travel.

6. Tighten the clamp nut.

Torque – Governor Arm Clamp Nut: 7.8 N·m (0.80 kg·m, 69 in·lb)

7. Be sure the governor shaft extends from the governor arm approximately 7 mm (0.3 in) [H] as shown.

8. Install the control panel assembly, and connect the governor arm with the governor spring.

Governor Assembly Removal

1. Remove the crankcase cover.

2. Remove the push rod.

3. Turn the engine upside down.

4. Remove the camshaft [A].

5. Remove the Washer [A], Snap Ring [B], Sleeve [C], Governor Plate [D], Steel balls [E], Ball Guide [F], and Ball Plate [G].

Governor Assembly Installation

1. Fit the snap rings into the grooves securely.

2. Spin the governor plate by hand and check that the steel balls and governor plate operate freely.

Low Idle Speed Adjustment

1. Disconnect all possible external loads from the engine.

2. Start the engine and warm it up thoroughly. Always keep your hands clear of moving parts.

3. Adjust the low idle speed screw [C] with a Phillips Screwdriver [D] until the engine idles at the specified speed.

Idle Speed (Carburetor idle rpm): 1450 rpm

4. Release the throttle lever and adjust the low idle speed set screw [B] on the control plate to obtain the specified governed low idle speed.

Low Idle Speed (Governed idle rpm): 1550 rpm

High Idle Speed Adjustment

NOTE: High idle speed adjustment should be made after the idle speed adjustment is performed.

CAUTION: Do not adjust high idle speed with the air cleaner removed.

1. Start and warm up the engine thoroughly. Always keep your hands clear of moving parts.

2. Move the throttle lever at the dash to the high idle position and match the lever hole position with the panel hole by inserting a 6 mm dia. pin or bolt [A].

3. Loosen the two M6 control panel mounting bolts [B] enough to move the control panel assembly.

4. Carefully move the control panel assembly right side [C] up or down to obtain the specified high idle speed.

High Idle Speed: 3600 rpm

5. Tighten the M6 Mounting bolts.

Torque – Control Panel Mounting Bolts: 5.9 N·m (0.60 kg·m, 52 in·lb)

6. Remove the 6 mm dia. pin or bolt.

7. Check the idle speed, and readjust if necessary.

At high altitude, the standard carburetor air-fuel mixture will be excessively rich, decreasing performance and increasing fuel consumption. To improve high altitude performance, install a smaller diameter main-jet in the carburetor and correct the idle speed. Main jet high altitude kits are available, and the numbers are stamped on the ends of the main jets.

High Altitude Main Jet Numbers for KAWASAKI FH641V

Main Jet Replacement Procedure:

1. Place the engine on a level surface and close the fuel shut-off valve.

2. Drain the fuel in the carburetor by unscrewing the drain screw.

3. Remove the carburetor.

4. Unscrew the main jet plugs [C] and take off the plugs and gaskets.

5. Make sure the “L” or “R” mark on the float chamber corresponds to the main jet position.

6. Using a proper blade screwdriver, carefully replace the main jet [D] with the new one for the expected altitude.

7. Tighten the main jet to the specification.

8. Install the gasket and the main jet plug.

Torque – Main Jet Plug: 19 N·m (1.9 kg·m, 14 ft·lb)

Follow these steps to test the fuel shut-off solenoid valve on the electric starter model of your KAWASAKI FH641V:

1. Unscrew the fuel shut-off valve and remove it from the carburetor.

2. Connect a 12 VDC source to the solenoid as shown in the manual’s diagram. The positive lead connects to the terminal and the negative lead connects to the body of the solenoid.

3. If the solenoid plunger (needle valve) does not pop in when the test voltage is applied, replace the valve.

NOTE: It may be necessary to push the plunger slightly for it to withdraw.

WARNING: Clean the carburetor in a well-ventilated area, and take care that there are no sparks or flames anywhere near the working area; this includes any appliance with a pilot light. Because of the danger of highly flammable liquids, do not use gasoline or low flash-point solvents to clean the carburetors.

CAUTION:

• Do not use compressed air on an assembled carburetor, or the floats may be crushed by the pressure.

• Remove as many rubber or plastic parts as possible before cleaning with a cleaning solution to prevent damage or deterioration.

• The carburetor body has plastic parts that cannot be removed. Do not use a strong carburetor cleaning solution which could attack these parts; instead, use a mild high flash-point cleaning solution safe for plastic parts.

• Do not use wire or any other hard instrument to clean carburetor parts, especially jets, as they may be damaged.

Cleaning Procedure:

1. Disassemble the carburetor.

2. Immerse all the carburetor metal parts in a carburetor cleaning solution and clean them.

3. Rinse the parts in water and dry them with compressed air.

4. Do not use rags or paper to dry parts, as lint may plug holes or passages.

5. Blow air through the holes and fuel passages with compressed air. All holes must be open.

6. Assemble the carburetor.

Element Removal

1. Remove the Air Cleaner Case Nut and Air Cleaner Case.

2. Remove the Wing Nut [A], Foam Element [B], and Paper Element [C].

Element Installation

1. Install the element correctly on the air cleaner body.

2. Be sure the paper element is in place in the air cleaner body.

3. Be sure the foam element is in place on the paper element body.

Element Cleaning and Inspection

NOTE: In dusty areas, the elements should be cleaned more frequently than the recommended intervals.

WARNING: Because of the danger of highly flammable liquids, do not use gasoline or a low flash-point solvent to clean the element.

1. Remove the foam element and the paper element.

2. Clean the foam element [A] in a bath of detergent and water, and let the element air-dry thoroughly before installing it.

3. Clean the paper element [B] by tapping it gently on a flat surface to remove dust. If the element is very dirty, replace it with a new one.

CAUTION: Do not use compressed air to clean the paper element. Do not oil the paper or foam element.

1. Before measuring, ensure the battery is fully charged and thoroughly warm up the engine. Then, stop the engine.

2. Disconnect the spark plug caps of each cylinder and remove the spark plugs.

3. Attach a compression gauge assembly firmly into one plug hole.

4. Ground the spark plugs to the engine. WARNING: To avoid fire, do not ground the spark plugs in proximity to the plug holes. Keep them as far away as possible.

5. Using the starter motor, turn the engine over with the throttle fully open until the compression gauge stops rising.

Cylinder Compression (MIN): 390 kPa (57 psi)

6. Repeat the measurement for the other cylinder.

If compression is too high, check for:

• Carbon build-up on the piston crown and cylinder head.

• Incorrect cylinder head gasket thickness.

• Worn valve guides and/or piston oil rings (indicated by white exhaust smoke).

If cylinder compression is lower than the minimum, check for:

• Gas leakage around the cylinder head (replace gasket, check for head warp).

• Condition of the valve seating.

• Incorrect valve clearance.

• Piston/cylinder wear or piston seizure.

• Piston ring or piston ring groove issues.

Valve Clearance Inspection

NOTE: Valve clearance must be checked when the engine is cold (at room temperature).

1. Remove the rocker cover.

2. Place the piston at top dead center (TDC) of the compression stroke by turning the crankshaft clockwise (facing the flywheel). Confirm TDC by observing the flywheel projection marks aligned with the ignition coil legs.

3. Check that both intake and exhaust valves are completely closed.

4. Using a thickness gauge, measure the valve clearance between the rocker arm and the valve stem end.

Valve Clearance (when cold) for Intake & Exhaust: 0.075 – 0.125 mm (0.003 – 0.005 in.)

5. If the clearance is incorrect, adjust it.

Valve Clearance Adjustment

1. With the piston at TDC of the compression stroke, loosen the lock screws [A] and valve clearance adjusting nuts [B].

2. Insert a thickness gauge [C] of the correct thickness between the rocker arm and valve stem.

3. Tighten the adjusting nut until the thickness gauge begins to bind. Use a sweeping motion with the gauge while adjusting.

4. Hold the adjusting nut with a spanner and tighten the lock screw to the specified torque.

Torque – Valve Clearance Lock screws: 6.9 N·m (0.70 kg·m, 61 in·lb)

5. Do not overtighten.

6. Remeasure the clearance and readjust if necessary.

Oil Level Inspection

1. Place the engine on a level surface.

2. Remove the oil filler cap [A] and wipe its dipstick [B] with a clean cloth.

3. Insert the dipstick into the tube [C] without screwing it in, then check the oil Level.

4. The oil level should be within the operating range [D] (grid area) on the dipstick.

5. If the oil level is in the “ADD” range [E], add enough specified engine oil to bring the level to the operating range.

CAUTION: Do not add more oil above the operating range. Excess oil will cause a smoking condition.

Oil Change

1. Change the oil after the first 8 hours of operation. Thereafter, change the oil every 100 hours.

2. Start and warm up the engine so the oil will drain easily, then stop the engine.

3. Place the engine on a level surface and place a suitable container under the engine.

4. Remove the drain plug [A] and drain the oil. WARNING: Be careful of hot oil when drained. It may be hot enough to burn you severely.

5. Check the O-ring [B] on the drain plug for damage and replace it if necessary.

6. Install the drain plug with the O-ring and tighten it.

Torque – Oil Drain Plug (Plastic): 6.9 N·m (0.7 kg·m, 61 in·lb)

Torque – Oil Drain Plug (Metal): 20 N·m (2.0 kg·m, 14.5 ft·lb)

7. Remove the oil filler cap and pour in the specified type and amount of oil. The oil grade should be SF, SG, SH or SJ class. Viscosity should be SAE40, SAE30, SAE10W-30/SAE10W-40, or SAE5W-20 depending on the ambient temperature. Capacity is 1.7 L (1.8 US qt) for models other than FH721V, and 1.8 L (1.9 US qt) for FH721V when the filter is removed.

Oil Filter Removal

1. Using an oil filter wrench (Special Tool: 57001–1249), remove the oil filter [B].

2. Place a suitable container beneath the oil filter to catch any oil that drains out.

3. Turn the filter counterclockwise to remove it.

Oil Filter Installation

1. Apply a light film of engine oil to the seal [A] of the new filter.

2. Install the new filter. Turn the filter until the seal contacts the mounting surface [B] of the engine.

3. Then turn the filter by hand an additional 3/4 turn.

4. Run the engine at a slow idle speed for 2 minutes and check for leaks around the engine.

5. Stop the engine and check the oil level, adding oil if necessary.

1. Install the ignition coil on the crankcase so that the stop switch lead connector [B] faces the screen.

2. Tighten bolt (1) first, then tighten bolt (2).

3. While tightening the bolts, adjust the air gap [A] between the three legs of the ignition coil and the two pole-plates of the magnet to the specified gap value.

Ignition Coil Air Gap (Standard): 0.2 – 0.4 mm (0.008 – 0.016 in.)

4. Tighten the bolts to the correct torque specification.

Torque – Ignition Coil Bolts (Stud Bolt): 7.8 N·m (0.80 kg·m, 69 in·lb)

Torque – Ignition Coil Bolts (Flanged Bolt): 5.9 N·m (0.6 kg·m, 52 in·lb)

NOTE: The above procedure must be used to ensure the proper coil air gap is not too large.

Spark Plug Cleaning and Inspection

1. Carefully pull the plug cap from the spark plug and remove the spark plug.

2. If the plug is oily or has carbon build-up, clean it using a high flash-point solvent and a wire brush or other suitable tool.

3. If the spark plug electrodes are corroded or damaged, or if the insulator is cracked, replace the plug. Use the standard spark plug (NGK BPR4ES) or its equivalent.

Spark Plug Gap Inspection

1. Measure the gap with a wire-type thickness gauge.

2. If the gap is incorrect, carefully bend the side electrode with a suitable tool to obtain the correct gap.

Spark Plug Gap (Standard): 0.75 mm (0.030 in.)

If your KAWASAKI FH641V engine is hard to start, follow these systematic steps:

1. Check for Spark: Remove the spark plug and turn over the engine while having the plug grounded against the engine block. WARNING: Keep the plug far away from the plug hole. To avoid an electric shock, do not hold the plug itself; hold the plug cap.

• Is spark produced?

• NO: Are you getting a spark when the ignition coil is replaced? If yes, the ignition coil was faulty (replace). If no, check for an incorrect air gap or a faulty flywheel (correct/replace).

• YES: Is spark produced when the original spark plug is replaced? If no, the original spark plug was faulty (replace). If yes, proceed to the next step.

2. Check Compression: Is compression sufficient?

• NO: Check for worn piston/piston rings, stuck piston rings, worn cylinder bore, insufficient cylinder head tightness, poor valve seating contact, warped cylinder head, wrong valve clearance, or a broken valve spring. Repair or replace as needed.

• YES: Proceed to the next step.

3. Check Fuel System: Make starting attempts a number of times and then remove the spark plug to observe the electrodes. Are they wet?

• NO (Dry Electrodes): This indicates a fuel delivery problem. Check for:

• No fuel in the tank (Add fuel).

• Entry of dust or air into the fuel line (Clean).

• Plugged air hole in the tank cap (Clean).

• Plugged fuel line (Clean).

• YES (Wet Electrodes): This indicates too much fuel. Check for:

• Excessive use of choke (Remove the plug and turn the crankshaft without loading).

• Plugged air cleaner (Clean).

• Too high fuel level in the float bowl (Adjust).

4. Check Carburetor: If the problem persists, check the carburetor for:

• A plugged fuel line.

• A plugged air passage.

• Incorrect float level.

• Incorrect carb setting.

If your KAWASAKI FH641V experiences a loss of power, follow this diagnostic procedure:

1. Is the engine overheated?

• YES: Check for low oil level in crankcase (adjust/add), too much oil (adjust), excessive brake load (decrease load), carburetor not properly adjusted (adjust), carbon deposit in combustion chamber (clean), clogging of cooling system (clean), or a damaged cooling fan (replace).

• NO: Proceed to the next step.

2. Is the ignition spark normal?

• NO: Check for a wrong spark plug (replace), faulty ignition coil (replace), or incorrect air gap (adjust).

• YES: Proceed to the next step.

3. Is lubrication condition normal?

• NO: Check for too much or too little oil in the crankcase (correct), or excessively contaminated lubricating oil (change).

• YES: Proceed to the next step.

4. Is there unusual smoke from the muffler?

• YES: Check for a plugged air cleaner (clean), carbon deposit in the exhaust hole and muffler (clean), carburetor not properly adjusted (adjust), too much oil in the crankcase (adjust level), worn piston/piston rings (replace), or a worn cylinder bore (bore/replace).

• NO: Proceed to the next step.

5. Is compression sufficient?

• NO: Refer to the steps for an engine that is hard to start.

First, disconnect the spark plug caps from the spark plugs. Then, turn the engine switch to “START” and check the condition. WARNING: The engine may be cranked in this test. Do not touch any rotating parts.

[STARTER DOES NOT ROTATE]

• Is there a “click” sound from the solenoid?

• NO: Check for a faulty battery (charge/replace), faulty leads or connection (repair/replace), melted fuse (replace), faulty engine switch (replace), or faulty solenoid (replace).

• YES: Check for a weak battery (charge/replace), faulty leads or connection to the motor (repair/replace), faulty solenoid switch (main terminal) (replace), or a faulty starter motor (repair/replace).

[STARTER ROTATES BUT SLOW]

• Is the battery normal and well charged?

• NO: The battery is weak (charge or replace).

• YES: Check for faulty leads or connection to the motor (repair/replace), faulty solenoid switch (main terminal) (replace), or a faulty starter motor (repair/replace).

[STARTER ROTATES BUT CAN NOT CRANK ENGINE]

• Does the pinion mesh with the ring gear?

• NO: Check for a worn pinion or ring gear (replace), or incorrect starter alignment (correct).

• YES: Check for a faulty pinion clutch (replace) or a faulty engine (repair/replace).

[STARTER DOES NOT STOP IN ENGINE SWITCH “OFF”]

• Can you stop the starter by turning the engine switch “OFF”?

• NO: Check for a faulty engine switch (repair/replace) or a faulty solenoid (repair/replace).

• YES: Check for a faulty pinion or ring gear (repair/replace), incorrect starter alignment (correct), or a faulty pinion return mechanism (repair/replace).