Kohler CH940 Generator Set

Tools: Tachometer

1. Check governed idle spring is in outer hole in governor lever and governed idle adjuster.
2. Check governor spring is in inner slot of governor lever and high speed adjuster.
3. Pull governor lever away from carburetor; turn high-speed screw counterclockwise until spring is loose.
4. Hold governor lever away from carburetor; start and warm engine.
5. Adjust inner screw to set approximately 1200 RPM; check with tachometer.
6. Release governor lever; check throttle lever is in idle position.
7. Turn governed idle outer screw to equipment manufacturer recommended idle speed 1500-1800 RPM.
8. Move throttle to wide-open/full throttle and set high speed screw to intended no-load RPM.

⚠ Do not tamper with governor setting. Overspeed is hazardous.

Tools: Long thin rod or tool

1. Make sure throttle linkage is connected to governor arm and carburetor throttle lever.
2. Loosen nut holding governor lever to cross shaft.
3. Move governor lever toward carburetor as far as it will go and hold at wide-open throttle.
4. Insert long thin rod or tool into hole on cross shaft and rotate clockwise as far as it will turn.
5. Torque nut to 7.1 N·m (63 in. lb.).

Tools: Tachometer

1. With engine running, move throttle control to fast.
2. Turn inner adjustment screw outward to decrease RPM or inward to increase RPM.
3. Stop when desired RPM is obtained.

Tools: Tachometer

1. Place throttle control into idle or slow position.
2. Turn low idle speed adjusting screw in or out to obtain 1200 RPM ± 75 RPM.

⚠ Rotating parts can cause severe injury. Stay away while engine is in operation.

Tools: Manometer or vacuum/pressure gauge, Rubber stopper

1. Insert rubber stopper into oil fill hole; connect manometer or vacuum gauge.
2. Start engine and run no-load high speed.
3. Open clamp and note water level or gauge reading.
4. Crankcase vacuum should be minimum 10.2 cm (4 in.) of water.
5. Close pinch clamp before stopping engine.

Tools: Cylinder leakdown tester, Breaker bar, Holding tool

1. Run engine 3-5 minutes to warm it up.
2. Remove spark plug(s) and air filter.
3. Rotate crankshaft until piston is at TDC of compression stroke.
4. Hold engine at TDC using holding tool or breaker bar.
5. Install adapter into spark plug hole; do not attach to tester yet.
6. Turn regulator knob completely counterclockwise.
7. Connect air source of at least 50 psi to tester.
8. Turn regulator clockwise until gauge needle is in yellow set area.
9. Connect tester quick-connect to adapter hose.
10. Hold engine at TDC; gradually open tester valve.
11. Note gauge reading and listen for escaping air at intake, exhaust, and crankcase breather.

⚠ Explosive fuel can cause fires and severe burns.

1. Disconnect and ground spark plug leads.
2. Close choke on carburetor.
3. Crank engine several times.
4. Remove spark plug and check for fuel at tip.
5. Remove fuel line from inlet fitting of fuel pump.
6. Hold line below tank bottom; open shut-off valve and observe flow.
7. Remove fuel line from inlet fitting of carburetor.
8. Crank engine several times and observe flow.

Tools: Continuity tester, Pressure regulator, Pressure gauge, Compressed air

1. Connect continuity tester across blade terminal and metal case.
2. With 0 psi applied, tester should indicate continuity.
3. Gradually increase pressure through 7-11 psi; tester should change to no continuity.
4. Switch should remain open up to 90 psi maximum.
5. Gradually decrease pressure through 7-11 psi; tester should change to continuity.
6. Replace switch if it does not operate as specified.

⚠ Do not leave 12 volt test leads connected longer than necessary.

Tools: 12 volt power supply, Test leads, Ohmmeter

1. Use a 12 volt power supply and 2 test leads.
2. Connect 1 lead to flat spade S/start terminal on solenoid.
3. Momentarily connect other lead to lower large post terminal.
4. Solenoid should energize with audible click and plunger should retract.
5. Repeat test several times.
6. Use ohmmeter on Rx2K scale across 2 large post terminals.
7. Perform actuation test and check for continuity.

1. Change oil while engine is warm.
2. Clean area around oil fill cap/dipstick and drain plug.
3. Remove drain plug and oil fill cap/dipstick; allow oil to drain completely.
4. Remove oil filter; wipe mounting surface.
5. Reinstall drain plug and torque to 21.4 N·m (16 ft. lb.).
6. Fill new filter with new oil; allow 2 minutes for absorption.
7. Apply thin film of clean oil to filter rubber gasket.
8. Install filter per instructions on filter.
9. Fill crankcase with new oil to top of indicator.
10. Reinstall oil fill cap/dipstick and tighten securely.
11. Start engine; check for leaks. Stop engine; correct leaks. Recheck oil level.
12. Dispose of used oil and filter per local ordinances.

⚠ Never run engine with oil level below or above operating range indicator on dipstick.

1. Ensure engine is cool. Clean oil fill/dipstick areas.
2. Remove dipstick; wipe oil off.
3. Reinsert dipstick into tube; press completely down.
4. Remove dipstick; check oil level at top of indicator.
5. Add oil if low; reinstall and secure dipstick.

⚠ Do not blow out paper element with compressed air.

1. Rotate element latch if equipped; remove paper element with precleaner.
2. Separate precleaner from element.
3. Service precleaner and replace paper element.
4. Install new paper element on base.
5. Install precleaner over paper element.
6. Rotate element latch if equipped.
7. Reinstall air cleaner cover and secure with knobs.