Generac Engine Slow Rev Up

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Joined: Tue Jul 09, 2019 10:10 am

Tue Jul 09, 2019 10:17 am

No sure how else to describe this, but my generac generator turns over, then slowly revs up to full RPM over about 20 or 30 seconds. Its a 16KW standby generator with the 992CC engine. Roughly 12 years old.

The symptoms are that it cranks strong, turns over, but then slowly revs up to full RPM. Once up to speed, it seems to run fine, but the really slow rev up is not normal. Sometimes it will not turn over, but usually does on the second try. Not sure if my description makes sense, but its olmost like its has trouble firing, barely "catches", the slowly comes up to full speed.

I changed spark plug, oil, airfilter, and the spark plug helped maybe a little bit, so wondering if it might be something related to this.

Any ideas would be appreciated.
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Location: Clawson, MI

Tue Jul 09, 2019 10:36 am

I'm basing this response on a guess that it's a 5243 model or similar (would need a serial number to confirm) but it sounds like the stepper motor has failed or is failing. It's what controls engine RPM and if they have stripped teeth internally or are weak, they will cause issues like this. It's also safe to assume that a large load applied would most likely result in a stall since the stepper motor (governor) can't respond quick enough.
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