Generac — Adjusting the Regulator (Natural Gas Only)
Adjustments · Fuel Regulator
From a Generac owner's manual — check it applies to your exact model before use.
Applies to: Generac GT-990 engine, Generac GH-410 engine
Before you start
- Do not remove any of the set pins.
- Be careful to avoid overspeeding the engine.
Procedure
- Turn off utility power to the main distribution panel.
- Allow the generator to start; confirm no load frequency is 63-63.5 Hz.
- Transfer load to emergency circuits and fully load the generator.
- Connect a frequency meter to the output lugs of the main line circuit breaker.
- Slowly turn the adjustment screws one at a time until the highest frequency is read.
- Turn both adjustment screws 1/4 turn counterclockwise.
- Turn utility power back on and allow the generator to shut down.
Tools required
- frequency meter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- No load frequency 63-63.5 Hz
- 11-14 FridayParts $35.69 inches water column fuel pressure
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.