Generac G-Force 1000 Series — Adjusting Valve Clearance
Adjustments · Valve train
For the Generac G-Force 1000 Series, from the Generac owner's manual.
Applies to: Generac G-Force 400 Series engine, Generac G-Force 800 Series engine, Generac G-Force 1000 Series engine
Before you start
- Risk of Burn. Allow the engine to cool before performing the following procedure.
Procedure
- Allow engine to cool before adjusting valve clearance.
- Remove spark plug wire(s) away from plugs and remove spark plug(s).
- Remove the four screws attaching the valve cover; remove and discard gasket.
- Verify piston is at TDC of its compression stroke (both valves closed).
- Loosen rocker jam nut using a 10 mm wrench (10 kW) or 13 mm wrench (20–22 kW).
- Turn pivot ball stud with a 14 mm wrench (10 kW) or 10 mm hex key (20–22 kW) while checking clearance with a feeler gauge.
- Hold pivot ball stud and tighten rocker arm jam nut to specification.
- After tightening jam nut, verify valve clearance did not change.
- Install new valve cover gasket and valve cover; tighten fasteners in a cross pattern.
- Install spark plugs and tighten to 18 ft-lbs (25 Nm).
- Attach spark plug wire to spark plug.
- Repeat process for other cylinder if equipped.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Rocker arm jam nut: 10 kW 53 in-lbs (6.0 Nm); 20–22 kW 174 in-lbs (19.68 Nm)
- Valve cover fasteners: 10 kW 80 in-lbs (9.0 Nm); 20–22 kW 60 in-lbs (6.8 Nm)
- Spark plug 18 ft-lbs (25 Nm)
Source: Generac owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.