Generac Generac OHVI Engine

Tools: Allen wrench, Feeler gauge, Crows foot

1. Ensure engine is at room temperature and piston is at TDC of compression stroke (both valves closed).
2. Loosen the rocker arm jam nut.
3. Use an allen wrench to turn the pivot ball stud while checking clearance with a feeler gauge.
4. When clearance is correct, hold the pivot ball stud and tighten the jam nut with a crows foot to 65-85 inch-pounds.
5. Recheck valve clearance to make sure it did not change.

Tools: feeler gauge, 8mm allen wrench, crow's foot torque wrench

1. Adjust valve clearance with engine at room temperature, piston at TDC of compression stroke (both valves closed)
2. Alternatively, position intake valve fully open to adjust exhaust valve, and exhaust valve fully open to adjust intake valve
3. Loosen rocker arm jam nut; turn pivot ball stud with 8mm allen wrench while checking clearance with feeler gauge
4. Tighten rocker arm jam nut to specified torque with crow's foot while holding pivot ball stud
5. Recheck valve clearance after tightening to ensure it did not change
6. Install new rocker arm cover gasket and reinstall cover with four screws; install oil breather tube

Tools: voltmeter

1. Set frequency to 62.5 Hertz with no load on the generator
2. Slowly turn the voltage adjust pot on the voltage regulator until 124 VAC is measured

Tools: cylinder leak down tester, compression gauge

1. Remove spark plug and valve cover
2. Rotate crankshaft to TDC with both valves closed; lock flywheel
3. Attach cylinder leak down tester adapter to spark plug hole
4. Connect air source of at least 90 psi; adjust regulated pressure to 80 psi
5. Read cylinder pressure gauge; 20 percent leakage is normally acceptable
6. Listen for air escaping at carburetor (intake valve), exhaust (exhaust valve), or breather (piston rings)
7. For compression check, insert compression gauge in spark plug hole and crank engine until pressure stops increasing

Tools: VOM, oil pressure gauge

1. Check engine oil level, replenish to FULL mark if necessary
2. Set VOM to Rx1 scale and zero meter
3. Connect meter leads across switch terminals with engine shut down; should read continuity
4. Crank engine; meter should read infinity once oil pressure opens switch contacts
5. If contacts do not open, remove switch and connect oil pressure gauge in its place; start engine and measure pressure

Tools: VOM, thermometer

1. Remove Wire No. 85 from switch terminal and start generator to isolate the fault
2. Remove switch and place sensing tip into oil with a thermometer
3. Connect VOM test leads across switch terminals; should read infinity
4. Heat oil; at approximately 305°F (151°C) switch contacts should close and meter should read continuity

⚠ Damage will result if the battery connections are made in reverse.

1. Connect the battery cable from the POSITIVE (POS or +) post to the lug on the starter contactor.
2. Check that the battery cable boot for the starter cable has been installed.
3. Connect the battery cable from the NEGATIVE (NEG or -) post to the frame ground connection.
4. Connect cables so the connectors are clean and tight.

⚠ DO NOT USE ANY FLAME TO TEST FOR LEAKS.

Tools: soap and water solution, separate 12 volt DC source

1. Do not place the generator into service until the gas system has been properly tested for leaks.
2. Provide a separate source of 12 volts DC to open the gaseous fuel solenoid valve.
3. Test all connections, hoses, valve regulators and fittings under gas or air pressure of not less than 90 psi (620 kPa).
4. Use soap and water or an equivalent solution to check for leaks.

⚠ You must not allow the unit to overheat during prolonged operation.

1. Apply electrical loads equal to about 75 to 100 percent of the unit's rated wattage/amperage capacity.
2. Let the unit run at least 30 minutes with load applied.
3. Check that the unit is not running excessively hot and that adequate cooling airflow is available.
4. Do not allow the unit to overheat during prolonged operation.

⚠ You must not allow the unit to overheat during prolonged operation.

1. Apply electrical loads equal to about 75 to 100 percent of the unit's rated wattage/amperage capacity.
2. Let the unit run at least 30 minutes with load applied.
3. Check that the unit is not running excessively hot and that adequate cooling airflow is available.

⚠ DO NOT FILL ABOVE THE 'FULL' MARK.

Tools: suitable container for oil, clean lint-free cloth

1. Run the engine until thoroughly warmed up (at least five minutes), then shut OFF the engine.
2. With the engine still warm, remove the oil drain plug and drain oil into a suitable container.
3. After the oil has drained, replace the oil drain plug (if only changing oil, go to step 7).
4. Remove the old oil filter by turning it counterclockwise.
5. Apply a light coating of clean engine oil to the gasket of the new filter.
6. Screw the new filter on by hand until its gasket lightly contacts the oil filter adapter; tighten an additional 3/4 to one turn.
7. Remove the dipstick and fill crankcase with proper oil; capacity about 1.8 liters or 1.9 quarts with filter change.
8. Install and tighten the dipstick before operating the engine.
9. Start the engine and check for leaks.

⚠ Never operate the engine with the oil level below the 'Add' mark.

⚠ DO NOT FILL ABOVE THE 'FULL' MARK.

Tools: clean lint-free cloth

1. Be sure the generator is as level as possible.
2. Remove the dipstick and wipe it dry with a clean, lint-free cloth.
3. Install and tighten the dipstick cap, then remove it again; oil should be at 'Full' mark.
4. If necessary, remove oil fill cap on rocker cover and slowly add oil to the 'Full' mark.
5. Install and tighten the oil fill cap and the dipstick before operating the engine.