Guardian/Generac 16k overspeed shutdown and start problem

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Robin
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Sun Oct 27, 2019 10:54 am

Unit identification: Model 0060631
Serial 7663632
Description: 16kw/990 CNT+200A SE T/S

Unit was installed and activated 01/19/2013.
Now has 108 hours on it. All from nor exercise.
The issue: During exercise period the unit shut down. The display showed "over-speed" and the red light on the side panel was on (still is). Moved switch to off then manual. Engine started (did not come up to speed) and shut down. Removed air filter and attempted restart. Choke shutter moved to cover intake port as expected.Engine cranked. Same result. Sprayed a little starting fluid in open intake port and attempted restart again. Engine started and RPM came up then died. The fuel for the unit is LP. I am not very familiar with LP fuel systems but I am suspecting fuel problem. Maybe over-speed sensing issue? What do you all think. Additional information: I have received a notification from Generac about a safety issue "Significant corrosion of the fuel plenum" suggesting an inspection. The local service rep has never showed up to perform an inspection for me. I doubt there is a corrosion problem but do not know for sure.
Chris
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Sun Oct 27, 2019 11:08 am

Being that it is on LP, I would start externally of the gen and work inwards.

Does the tank have fuel? If so, is the regulator outputting the correct fuel pressure to the generator?
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Robin
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Sat Nov 02, 2019 1:56 pm

Update:
The fuel pressure from supply tank to generator is 12 in water column. Connected gage to generator regulator, no pressure. Moved control switch to manual engine began to crank, gage showed 11 to 12 then momentarily decreased , engine tried to start making loud popping sounds and vibrating rough, pressure back up, engine shut down, display reads RPM sense loss.
Chris
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Sat Nov 02, 2019 5:42 pm

The backfiring leads me to believe that it needs new ignition coils...

They are also what give the controller its ignition signal for the RPM Loss alarm through the 18 wire.

There is a replacement kit available here: https://shop.gentekpower.com/products/g ... generators

I will warn however, it's not a fun project...
Generac tech for over 12 years. I'm here to help!
"The only source of knowledge is experience" -Albert Einstein
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A list of my favorite Generator & Electrical Tools! https://www.amazon.com/shop/gentek_power
Robin
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Sun Nov 10, 2019 11:58 am

Isolating the cylinders by alternately disconnecting the spark plug wires the engine will start and come up to speed and run smoothly on #2 cylinder. It will not start on #1 cylinder, it tends to attempt then sputters and dies.
Robin
Chris
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Mon Nov 11, 2019 8:36 pm

That basically confirms my ignition coil theory. :sad:
Generac tech for over 12 years. I'm here to help!
"The only source of knowledge is experience" -Albert Einstein
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Birken Vogt
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Mon Nov 11, 2019 9:55 pm

He has not adjusted the valves yet correct? First thing always before condemning parts.
Chris
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Tue Nov 12, 2019 9:36 am

Birken is right. I should not have assumed with 108 hours that the valves wouldn't need adjustment. They normally wouldn't, but it's an easy and cheap check!
Generac tech for over 12 years. I'm here to help!
"The only source of knowledge is experience" -Albert Einstein
Looking for Generac parts? Gentek Power offers the full line of Generac replacement parts! Shop Gentek Power Generac Parts
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Robin
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Tue Nov 12, 2019 11:40 am

My mistake,
Correct hours is 80. Valve adjustment is correct to specs. compression is correct.
Robin
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