Generac Generator Overcrank Alarm — Fix Guide

What it means

Overcrank means the Generac starter cranked the engine multiple times but it did not fire.
Check the fuel supply, spark plug, and battery as the first steps.

How to Fix It

Check the fuel supply

Confirm that natural gas or propane is flowing.
Check that the gas shutoff valve on the supply line is fully open and your gas service is live.
Check fuel pressure

Low gas pressure from the utility or a nearly empty propane tank prevents the engine from starting.
For propane, check the tank gauge.
Below 20% tank level can cause pressure issues.
Inspect the spark plug

Remove the spark plug (single plug on air-cooled models).
Check for carbon fouling, cracks, or a worn electrode.
Replace if in doubt — spark plugs are inexpensive.
Check the battery

A weak starter battery cranks the engine slowly, making it harder to start.
Test battery voltage (should be 12.6V or above).
Slow cranking often causes overcrank faults.
Inspect the choke

The automatic choke should close on a cold engine to enrich the mixture.
A seized choke plate can prevent the engine from catching.
Check for free movement.
Check the carburetor

If the generator sat unused for months with old fuel, varnish deposits can block the carburetor jets.
Clean or replace the carburetor, or use a fuel system cleaner.

Frequently Asked Questions

What does overcrank mean on a Generac generator?

Overcrank means the starter motor spun the engine for the maximum allowed time without it starting.
The control board stops cranking to protect the battery and starter motor.

How do I reset an overcrank alarm on Generac?

After fixing the cause, press RESET on the generator control panel or use the Generac Mobile Link app.
Then switch back to AUTO mode for normal operation.

Can cold weather cause overcrank on a Generac?

Yes — in very cold conditions, thickened oil and reduced battery capacity make starting difficult.
Ensure the battery is fully charged and use the recommended winter-grade oil.