Briggs and Stratton 20KW - Shuts down

Briggs & Stratton generator troubleshooting
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Joined: Tue Jan 05, 2021 1:23 pm

I have a B&S 20Kw LNG/Propane standby Generator that will start and turn off after 5-6 seconds. After 5 attempts to start it will produce a code FC-4 for "engine fails to start". The generator seems to be sensing
a problem and wants to shut down. The LNG input has a gauge and measures slightly over 8" water column so I ti not low on fuel. The voltage measured coming from the generator at the breaker on the generator is on 70 volts when it is running for those 5 seconds. Does this mean the stator is bad? Is there a voltage regulator I can test? Could the circuit board be the issue? Anyone else have a similar problem?
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Location: Clawson, MI

Have you measured on both sides of the circuit breaker (generator side as well as load side)? These will show that fault if the breaker is off I believe as well, since they're measuring output voltage after the breaker for some odd reason...

It's likely a bad voltage regulator since you're making some voltage. We don't sell B&S parts, but with a model number we can probably help track something down for you.
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