Onan should be the name of a dog: Rough Ruff...

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Seeburg220

Seeburg220

Active member
Oct 25, 2021
318
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43
Berryville, VA
My Pertronix gave out and I'm in the process of getting a new one. In the meantime, I hooked back up the points. This is the reason I went to electronic ignition. It's a little hard to tell from the video, but it's running like crap. The points are gapped at .020, as per the book. Adjusting the gap seems to make no difference. My only guess is, the pushrod that cycles the points open and closed, is worn, warped, loose or just tired. The coil has been replaced and makes no difference between the two. The plugs are new and gapped at .020 also. I was hoping to squeak by with the points until I have a new Pertronix in hand.

 
Seeburg220 said:
My Pertronix gave out and I'm in the process of getting a new one. In the meantime, I hooked back up the points. This is the reason I went to electronic ignition. It's a little hard to tell from the video, but it's running like crap. The points are gapped at .020, as per the book. Adjusting the gap seems to make no difference. My only guess is, the pushrod that cycles the points open and closed, is worn, warped, loose or just tired. The coil has been replaced and makes no difference between the two. The plugs are new and gapped at .020 also. I was hoping to squeak by with the points until I have a new Pertronix in hand.

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The Onan should run just as well with new points and condenser as it does with the pertronix.
 
Our backup Onan used last night and part of today while the power was out. This one has a Ford crankshaft sensor where the Pertronix was (pertronix quit on me too) with a Crane ignition box and a GM wasted spark coil. I have the same ignition set up on the GMC's Onan. Running .045 spark gap.
 
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Wally said:
Our backup Onan used last night and part of today while the power was out. This one has a Ford crankshaft sensor where the Pertronix was (pertronix quit on me too) with a Crane ignition box and a GM wasted spark coil. I have the same ignition set up on the GMC's Onan. Running .045 spark gap.
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That's excellent. I'm not savvy enough to figure that out, unless it's plug and play.
 
Wally said:
Our backup Onan used last night and part of today while the power was out. This one has a Ford crankshaft sensor where the Pertronix was (pertronix quit on me too) with a Crane ignition box and a GM wasted spark coil. I have the same ignition set up on the GMC's Onan. Running .045 spark gap.
Click to expand...
Do you have EFI on this one too Wally?
 
If your points are the type that can be adjusted in place, Start the onan and start cranking on the adjustment screw with it tunng until you find the smoothest running spot. Also since you have not been using them for a while clean the contact surfaces with a march book cover soaked in alcohol.
tmsnyder said:
Does the crank trigger have to be a certain number of degrees btdc?
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You want it mounted so the spark fires at 26 or 27 BTDC I did some experiments one time and it ran fine but that is dangerously close to the detonation point.

Keep in mind that this is a static setting and the engine runs at a continuous 1800 RPM, so higher advance numbers do not apply.
 
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Update: I sent my module to Gary and he tested it and sent it back. I reinstalled it per the written instructions and it fired right up. I'm guessing there was a ground issue and reinstalling it seems to have fixed it. The problem now is, it just doesn't run smooth. It's not the module, as it was running poorly with the points as well.
I adjusted the carb per the Onan book, new plugs gapped at .020, cleaned carb, fuel pump, checked for fuel to the carb.
The only thing I haven't done yet, is check the float level. It seems to smell rich. I set the timing yesterday when I reinstalled the module, I believe it's 25 or 26 degrees. There's a mark on the flywheel that I highlighted a year ago and I had that mark centered in the viewing hole.
Man, if I had an extra $5k, I'd be buying a new generator. So tired of this damn thing.

 
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Heads torqued to 19lbs in the pattern?
Voltage regulator disconnected and taped off?
Crankcase vent tube not internally collapsed.

Disconnect the top remote wires on the control board and try it

call in a priest?
 
Don Jaksa said:
Heads torqued to 19lbs in the pattern?
Voltage regulator disconnected and taped off?
Crankcase vent tube not internally collapsed.

Disconnect the top remote wires on the control board and try it

call in a priest?
Click to expand...
They were torqued when I had the heads off a year and half ago. Haven't checked since. Voltage reg. is disconnected. Wires not taped off, but not touching anything either. Crankcase tube is new and in good condition. Which top wires to remove? All of them? Thanks.
 
All the wires on the top of the control board are for the remote indoor operation.
Disconnect them to eliminate some shorting problem as a test

Bang on the carb to dislodge the particles

These are all MIR space station approved technical diagnostics
 
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