Generac 20 kW 3-Phase Generator Set

⚠ Allow engine to cool before adjusting valve clearance

Tools: 13 mm wrench, 10 mm Allen wrench, Feeler gauge, Torque wrench

1. Remove spark plug wire(s) and position away from plugs.
2. Remove spark plug(s).
3. Remove the four screws attaching the valve cover.
4. Remove and discard the valve cover gasket.
5. Make sure the piston is at top dead center (TDC) of its compression stroke.
6. Remove the intake screen at the front of the engine to access the flywheel nut.
7. Use a large socket and wrench to rotate the flywheel nut clockwise to position the piston at TDC.
8. Loosen the rocker jam nut using a 13 mm wrench.
9. Turn the pivot ball stud using a 10 mm Allen wrench while checking clearance.
10. Adjust clearance to 0.002–0.004 in using a feeler gauge.
11. Hold the pivot ball stud in place with a wrench and tighten the rocker arm jam nut to 174 in-lbs (19.68 Nm).
12. Recheck valve clearance to verify it did not change.
13. Install new valve cover gasket.
14. Install the valve cover and tighten fasteners in a cross pattern to 60 in-lbs (6.8 Nm).
15. Install spark plugs and torque to 18 ft-lbs (25 Nm).

⚠ Disconnect negative battery cable first

⚠ Do not use tap water for battery

⚠ Remove jewelry and use insulated tools

Tools: Wrench for battery terminals

1. Lift the lid and press the OFF button to shut down the generator.
2. Remove the front panel.
3. Remove the 7.5 amp fuse from the control panel.
4. Remove the intake side panel.
5. Disconnect the white battery charger cable.
6. Inspect the battery posts and cables for tightness and corrosion.
7. Tighten and clean as necessary.
8. For unsealed batteries only: Disconnect the battery completely.
9. Check the battery fluid level and fill with distilled water only if necessary.
10. Have an IASD or qualified service technician check the state of charge and condition.
11. Reconnect the battery cables and battery charger cable.
12. Reinstall the intake side panel.
13. Reinstall the 7.5 amp fuse.
14. Place the controller in AUTO mode.
15. Complete the Installation Wizard Menu.

⚠ Allow engine to cool before draining oil

Tools: Oil drain hose, Oil filter wrench, Oil collection container, Clean cloth

1. Press the MANUAL button on the control panel to start the engine.
2. Run the engine until it is thoroughly warmed up.
3. Press the OFF button to shut down the engine.
4. Allow the engine to cool slightly.
5. Lift the lid and remove the front panel.
6. Pull the oil drain hose free of its retaining clip.
7. Remove the cap from the hose and drain the oil into a suitable container.
8. Replace the cap after draining and secure the hose with the retaining clip.
9. Remove the old oil filter by turning it counterclockwise.
10. Apply a light coating of clean engine oil to the gasket of the new filter.
11. Screw the new filter on by hand until its gasket lightly contacts, then tighten an additional 3/4 to one full turn.
12. Refill the engine with the proper recommended oil.
13. Press the MANUAL button to start the engine and run for one minute.
14. Check for leaks and press the OFF button to stop the engine.
15. Wait five minutes and recheck the oil level.

Tools: Oil dipstick, Clean cloth

1. Run the generator for approximately one minute cool-down period.
2. Turn the main utility disconnect off.
3. Turn the main line circuit breaker (MLCB) on the generator to OFF (OPEN).
4. Turn the generator off and press the OFF button.
5. Wait five minutes.
6. Remove the oil dipstick and wipe it dry with a clean cloth.
7. Completely insert the oil dipstick into the oil dipstick tube and remove it.
8. Observe the oil level; should be at the FULL mark.
9. If necessary, remove the oil fill cap and add oil until reaching the FULL mark.
10. Insert the oil dipstick and fill cap back in place.

⚠ Fuel and vapors are extremely flammable and explosive

Tools: Clean-out tool, Pipe wrench, Gas leak detection fluid

1. Lift the lid and press the OFF button to shut down the generator.
2. Remove the front panel.
3. Remove the intake side panel.
4. Turn the generator fuel supply off.
5. Remove the battery.
6. Unscrew and remove the sediment trap cap.
7. Use a clean-out tool to remove accumulated moisture and particles from the cap and body.
8. Wipe the inside of each component with a clean, dry, lint-free cloth.
9. Seal the threads of the cap with appropriate sealing compound.
10. Install the cap and hand-tighten.
11. Tighten the cap with an appropriately sized pipe wrench without overtightening.
12. Turn the generator fuel supply on.
13. Check for leaks by spraying all connection points with non-corrosive gas leak detection fluid.
14. Install the battery.
15. Install the intake side panel, put the generator into AUTO mode and close the lid.

Tools: Screwdriver for cover clips

1. Press the OFF button on the control panel to stop the generator.
2. Lift the lid and remove the front panel.
3. Remove the cover clips and air cleaner cover.
4. Remove the old air filter element and discard it.
5. Thoroughly clean the air cleaner enclosure of any dust or debris.
6. Install a new air filter element.
7. Install the air cleaner cover and fasten the cover clips.
8. Verify that the air inlet duct is properly connected to the air cleaner cover.
9. Press the AUTO button on the control panel to return to AUTO mode.

Tools: Wire feeler gauge, Socket and torque wrench

1. With the generator OFF and the engine cool, lift the lid and remove the front panel.
2. Clean the area around the base of the spark plugs to keep dirt and debris out.
3. Remove the spark plugs and check their condition.
4. Install new plugs if the old plugs are worn or questionable.
5. Clean the plugs by scraping or washing with a wire brush and commercial solvent.
6. Do not blast the plugs to clean.
7. Check the spark plug gap using a wire feeler gauge.
8. Replace the spark plug if the gap is out of specification.
9. Reinstall the spark plugs and torque to 18.4 ft-lbs (25 Nm).
10. Press the control panel AUTO button to return to AUTO mode.