Community Forums

bduemig · 06-16-2022, 08:14 PM

My generator runs great until it gets very hot outside. It runs for a while, then loses all ac power. It stays off for a minute or so, then comes back on. It does it 2 or 3 times, then I need to shut down the generator and restart
Then the same thing happens until it cools off then fund good until it gets hot. Temp outside today was 102 when it stopped working.

Is there a thermal cutoff switch on these generators?

153stars · 06-17-2022, 01:45 AM

Down load manual . shows how to retrieve fault codes . Its common for high temp and oil pressures switches to get bad. Don't 100% trust antifreeze level in recovery tank ,if caps get old it can stop drawing liquid back when engine cools, pull rad cap to check for sure. The radiator can get dirty and there's a fan belt that runs the radiator fan can get old.
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Tha_Rooster · 06-18-2022, 05:24 AM

Quote:

Originally Posted by bduemig

My generator runs great until it gets very hot outside. It runs for a while, then loses all ac power. It stays off for a minute or so, then comes back on. It does it 2 or 3 times, then I need to shut down the generator and restart
Then the same thing happens until it cools off then fund good until it gets hot. Temp outside today was 102 when it stopped working.

Is there a thermal cutoff switch on these generators?

Is it throwing codes?

bduemig · 06-19-2022, 04:47 AM

My.manual doesn't show how our if I can retract codes. I did pull the radiator cap and found coolant level low but the overflow tank.was full. I need to get b the specs on the cap and order va new one.

Randy125 · 06-19-2022, 07:29 AM

Look at the voltage regulator, might be failing due to heat.

bduemig · 06-20-2022, 04:44 PM

Thank you. I will n check the voltage regulator

bduemig · 07-07-2022, 12:36 PM

Well, it is not the voltage regulator or the circuit breaker next to it.

Is out time to take it to a shop or is there something else I can check?

153stars · 07-07-2022, 07:44 PM

The psi should be on cap auto parts will have one. Most common issues is to stop drawing back fluid from expansion tank.once they get large air pocket in the top it stops working. Then just compresses air like old large top tank radiators worked before recover tanks. Problem is these new engines and radiators are designed to be free of even the smallest air pockets.
You need to retrieve codes. There are repair and diagnostic manuals online for practical all RV Onan generators online.
Before smart ones with codes was common to just replace temp and out pressure switch if there was a problem.
.An exhaust leak caused my radiator to plug up with carbon on my 75D Generac. With all the covers off I replaced , brushes, inline fuel strainer,weak starter,alt. belt . The fan belt looked new. I repaired exhaust flex pipe with stainless NPT pipe much higher quality rated over 100psi.

Randy125 · 07-08-2022, 05:54 AM

Generac doesn’t have retrievable codes.

THenne1713 · 07-10-2022, 09:22 AM

If 75D is water cooled, thermals should shut down engine, not electric, in my diesel experience, so if just doing electric, I would more suspect a circuit board solder issue, or loose wire somewhere that is disconnecting under higher loads? CAN BE a SCREW connection, or a PUSH-ON at a circuit board, or a simple circuit board loose solder joint?