jamesgang423
Generac 7 kW Propane  Model 0065190, SN 9290576

Unit never starts on first attempt. runs beautifully after starting. Occasionally, won't start after third attempt.

Generac installer stated fuel problem was the issue, had supply pressure & volume re-certified by gas company, all good.

Found that by manually helping "choke butterfly" to open unit will start every time, without fail. Found sticking "choke butterfly", caused by mis-aligned solenoid.  Re-aligned solenoid, butterfly now free. Unit still has irregular starting, and will start EVERY time if butterfly is helped to open just a second or two before the end of the crank cycle. 

As I understand it, the butterfly closes until a vacuum is detected by fuel flow through the demand regulator? I'm guessing there's a sensor to detect it and then trigger the solenoid to release? I've heard about modifying the demand regulator spring, for possibly being too stiff, but am very reluctant to begin messing around with that.

Any help would be appreciated!
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exrace
Possible the stepper controller is having problems. I had an issue with my 20kw unit when the stepper controller connector had a bad connection.
Try unplugging and plugging in the stepper connector a few times to reduce the possibility the connector has a high resistance connection.
The troubleshooting manual also has details on checks for this device electrically.
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murphy
Does this model have a rubber bellows between the air box and the carburetor?  If it does check it carefully for holes in the rubber especially at the bottom of the folds.
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DanS26
Try adjusting the butterfly linkage so that the valve does not close all the way, thus avoiding the sticking problem.  The underlying problem is that the housing is out of round causing the plate to stick at a certain point.

A couple of washers or shims in the right place could solve your problem.
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Geoff Z
This unit is a 7kw PowerPact. See attached
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MacL
This is a single cylinder engine with a mechanical governor....no stepper motor on board, so don't be looking for that.

Take a jumper wire and connect it from the positive side of the fuel solenoid to battery positive.  You should not hear or smell any gas flow.  If it does flow it will be coming into the carburetor (mixer), and may be muffled and hard to hear or smell.  If it does flow, you have a stuck or damaged valve inside the demand regulator.

If it is all quiet, which is good, with some vice grips and two flat pieces of strong metal, kink the the fuel hose above the demand regulator.  Energize the fuel solenoid and leave energized.  Take a dull tool such as a 4 mm allen wrench or smaller and press the diaphragm through the cover.  No fuel should flow.  If you feel it blowing past your wrench while pressing, the diaphragm is perforated.  (Be sure your pliers are extremely tight; it's hard to smash those hoses.  Gas flow at this point may be making it past your kink.)

So in the first test you've checked for proper closure of the diaphragm valve, and in the second test you've checked your diaphragm for holes or cover gasket leaks.
State your problem, not your diagnosis.
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nrp3
Which control board does it have?  A or B.  The A, if I remember takes a couple of attempts to start and manipulates the choke differently than the B.  The B seemed to produce a more normal start.  Not sure if this worked properly before or not.
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jamesgang423
I’ll check, this issue has been there since it was installed.
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jamesgang423
Butterfly no longer sticking after solenoid adjustments.
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jamesgang423
No it does not
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