Generac 04675-3 Adjusting Valve Clearance, Cooling System, 10 - Valve Clearance Adjustment

Section 4 — Maintenance

Generac Air-cooled 7 kW, 12 kW and 15 kW Generators

4.8ADJUSTING VALVE CLEARANCE

After the first 50 hours of operation, adjust the valve clearance in the engine.

Important: If feeling uncomfortable about doing this procedure or the proper tools are not available, contact the nearest Generac Authorized dealer for service assis- tance. This is a very important step to insure longest life for the engine.

To adjust valve clearance:

•Make sure the engine is at room temperature.

•Make sure that the spark plug wire is removed from the spark plug and out of the way.

•Remove the four screws attaching the valve cover with a #2 or #3 phillips screwdriver.

•Make sure the piston is at Top Dead Center (TDC) of its compression stroke (both valves closed). To get the piston at TDC, remove the intake screen at the front of the engine to gain access to the flywheel nut. Use a large socket and socket wrench to rotate the nut and hence the engine. While watching the piston through the spark plug hole. The piston should move up and down. The piston is at TDC when it is up as high as it can go.

•Loosen the rocker jam nut. Use an 10mm allen wrench to turn the pivot ball stud while checking clearance between the rocker arm and the valve stem with a feeler gauge. Correct clearance is 0.002-0.004 inch (0.05-0.1 mm).

NOTE:

Hold the rocker arm jam nut in place as the pivot ball stud is turned.

When valve clearance is correct, hold the pivot ball stud in place with the allen wrench and tighten the rocker arm jam nut. Tighten the jam nut to 174 in/lbs. torque. After tightening the jam nut, recheck valve clearance to make sure it did not change.

Figure 4.10 - Valve Clearance Adjustment

Rocker

Pivot BallArm

Stud

Jam Nut

Valve

Stem

•Install new valve cover gasket.

•Re-attach the valve cover. NOTE:

Start all four screws before tightening or it will not be possible to get all the screws in place. Make sure the valve cover gasket is in place.

•Re-attach the spark plug wire to the spark plug.

•Repeat the process for the other cylinder.

4.9COOLING SYSTEM

Air inlet and outlet openings in the generator compart- ment must be open and unobstructed for continued proper operation. This includes such obstructions as high grass, weeds, brush, leaves and snow.

Without sufficient cooling and ventilating air flow, the engine/generator quickly overheats, which causes it to quickly shut down. (See Figure 4.9 for vent locations.)

Figure 4.9 – Cooling Vent Locations

The exhaust from this product gets extremely hot and remains hot after shutdown. High grass, weeds, brush, leaves, etc. must remain clear of the exhaust. Such materials may ignite and burn from the heat of the exhaust system.

The maximum ambient temperature for the

!generator is 48.9° C (104° F).

20 Generac® Power Systems, Inc.