Kohler MV20 Generator Set

⚠ Do not force tapered adjusting needles.

Tools: Tachometer

1. Turn idle fuel adjusting needle in until it bottoms lightly.
2. Set preliminary needle settings.
3. Start engine and run at half throttle 5-10 minutes.
4. Set main fuel needle midway between rich and lean if adjustable.
5. Set idle speed to 1200 rpm by turning idle speed screw.
6. Set idle fuel needle midway between rich and lean.
7. Recheck idle speed with tachometer.

⚠ Engine must be cold when checking clearance.

Tools: Flat feeler gauge

1. Remove air cleaner, valve covers, breather, and spark plugs.
2. Rotate flywheel; determine which cylinder is at TDC.
3. Measure clearance with flat feeler gauge.
4. If too small, remove valves and grind valve stems.
5. If too large, replace valves and recheck clearance.
6. Reinstall spark plugs, breather, valve covers, and air cleaner.

⚠ Never tamper with governor settings to increase maximum speed.

Tools: Pliers, Tachometer

1. Pull governor arm down and away from carburetor.
2. Grasp cross shaft with pliers and turn clockwise fully.
3. Tighten hex nut on governor arm to 15 in. lb.
4. Adjust high speed stop to desired speed.
5. Recheck speed with tachometer.

Tools: Compression tester

1. Remove spark plugs and install compression tester in each hole.
2. Set throttle and choke controls wide open.
3. Make sure air cleaner and exhaust are not restricted.
4. Crank engine using starting motor and take readings for both cylinders.
5. If difference is 15% or greater, or pressure is less than 90 psig, inspect further.

Tools: Slack tube manometer

1. Insert stopper/hose into oil fill hole; leave manometer vent open.
2. Start engine and run at high speed 3200 to 3750 rpm.
3. Open clamp and note water level in tube.
4. Engine side should be 7 to 14 in. above open side.
5. Close shutoff clamp before stopping engine.

⚠ Zero ohmmeter on each scale before testing.

Tools: Ohmmeter

1. Measure primary resistance from kill terminal B to laminations A.
2. Primary resistance should be 5 to 1000 ohms one direction.
3. Reverse leads; primary resistance should be 30,000 ohms minimum.
4. Measure secondary resistance between leads C and D.
5. Secondary resistance should be 22,000/42,000 ohms.
6. Replace module if readings are out of range.

1. Make sure engine is stopped, level, and cool.
2. Remove oil fill cap/dipstick and oil drain plug.
3. Drain oil while engine is warm.
4. Reinstall drain plug and tighten securely.
5. Fill with proper oil to F mark on dipstick.
6. Check level before adding more oil.

1. Drain crankcase oil, then remove old filter.
2. Apply thin coating of oil on rubber seal.
3. Turn filter clockwise until seal contacts adapter.
4. Tighten filter additional 1/2 turn.
5. Add additional 1/2 pint of oil for filter capacity.
6. Start engine and check for oil leaks.

Tools: Wire feeler gauge

1. Clean area around base of plugs.
2. Remove plugs and check condition.
3. Check gaps using wire feeler gauge.
4. Adjust gaps to 0.025 in. by bending ground electrode.
5. Reinstall plugs into cylinder heads.
6. Torque plugs to 10/15 ft. lb.

⚠ Do not wash paper element or use compressed air.

1. Remove precleaner, element cover seal, element cover, and paper element.
2. Replace dirty, bent, or damaged element with new genuine Kohler element.
3. Reinstall paper element, element cover, and element cover seal.
4. Reinstall precleaner over paper element.
5. Install air cleaner cover and wing nut; tighten 1/2 to 1 full turn.

1. Remove precleaner from paper element.
2. Wash precleaner in warm water with detergent.
3. Rinse thoroughly and squeeze out excess water.
4. Allow precleaner to air dry.
5. Saturate precleaner in clean engine oil.
6. Squeeze out excess oil and reinstall over paper element.

⚠ Kohler starter drive lubricant must be used.

Tools: Vise with soft jaws

1. Remove starter from crankcase.
2. Remove dust cover, stop nut, stop gear spacer, spring, dust cover spacer, and drive pinion.
3. Clean drive shaft splines with solvent and dry thoroughly.
4. Apply Kohler electric starter drive lubricant Part No. 52 357 01 to splines.
5. Apply Loctite No. 271 to stop nut threads.
6. Reassemble drive parts; torque stop nut to 160 in. lb.
7. Reinstall starter to crankcase.