8KW Diesel Starter Comes Back On While Running

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The Grand Pooh-Bah
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Location: Idaho

My 8KW 1.0L Diesel generator will start up OK. Then the starter kicks in again after it is running. I was told that it was either low oil pressure or a defective oil Pressure switch. I added a oil pressure gauge 45PSI and replace the oil pressure switch with a normally closed switch that opens at 8 PSI. I even tried disconnecting wire 85 to the control board after it started, to rule out that one of the other safeties wasn't triggering this. It appears something else is telling the start sequence that the generator isn't running..... Need ideas where to look.
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Generac 8KW Model 00449-0 Engine # 70939 1.0 L Shibaura S753 Alternator Data: Model 00449-0 SN 3113852 120/240v 1800 RPM
The Grand Pooh-Bah
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Joined: Mon Jun 17, 2019 1:03 am
Location: Idaho

I have since learned that most of these units actually sense voltage for the starter to disengage. Can someone tell me which wire sends this signal back to the control board to verify that the engine has started? I have the Generac 076009ASRV Engine Control board.
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Generac 8KW Model 00449-0 Engine # 70939 1.0 L Shibaura S753 Alternator Data: Model 00449-0 SN 3113852 120/240v 1800 RPM
Chris
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There is a winding in the stator that tells the controller that the unit is running. I think you'll likely find there is no output at the breaker either!
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The Grand Pooh-Bah
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Location: Idaho

I'm currently at the generator. Started it up with fluke connected to the S15 & S16 leads, at the common lead and power on one leg of the breaker. When it started it was at 320v then went to 168v and starter stoped, then it went to 320v again and starter kicked back on. This all took place within a few seconds and I turned it off.
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Generac 8KW Model 00449-0 Engine # 70939 1.0 L Shibaura S753 Alternator Data: Model 00449-0 SN 3113852 120/240v 1800 RPM
Chris
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Sounds like a bad voltage regulator to me, and the DPE breaker is opening to protect the DPE winding and then it's cooling off and closing again and the voltage is spiking back up.
Generac tech for over 12 years. I'm here to help!
"The only source of knowledge is experience" -Albert Einstein
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