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Onan BGE - Only runs while holding the start button then shuts off when released

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I have been reading posts about troubleshooting the BGE. I've downloaded the user, service, and parts manuals for it, and I downloaded the flight systems troubleshooting guide. I have the "starts but dies when you let off the start switch" condition that Flight Systems says is a common issue.
I applied 12V directly to the coil and fuel pump and the generator runs fine, but will not run on its own.
I replaced the printed circuit board and rectifier bridge -still fires with the start switch pushed in and dies when you let go..
I removed the shrouding around the oil filter and checked continuity of the LOP wire. It was good, so I attached it directly to ground - still fires with the start switch pushed in and dies when you let go.
I check the 2.5 ohm resistor as the manual said to do. It read 2.7. I kinda shook the generator to try to see if it was an intermittent connection, but it stayed solid.
Now I am to the point in the Flight systems guide that says to check voltage B1-B2. Where is a good place to access these?

thanks in advaince

You "grounded" the LOP switch? That does not sound right. To test the switch you would connect the two wires together on a two wire switch. Not sure what pressure switch you have, the bigger Onans have a two wire switch. I will look up the diagram.

Looked at the manual but it is not real clear on the switch. It looks to me like the switch has two wires and if that is the case then I am guessing if you connect them together it will run. That is simulating a closed oil pressure switch. If that is the case you HAVE to verify that you do actually have oil pressure and that it is just a bad switch. Do not keep running it that way until you know for sure that you have oil pressure.

It is a single-wire switch - I've read in other posts where the resting state of the switch is open, then when the lubrication system pressurizes, it grounds. Since my initial post, I've verified that's how mine is working.
At this point I'm pretty sure it's the generator part that isn't working, and that's bad because it's the part I know absolutely nothing about. I see in the flight systems troubleshooting that I'm supposed to check voltage B1-B2. On the diagrams in the service manual, B1 is the wire to the starter on some diagrams pertaining to the control, but I don't see a B2 on those. In the actual generator section, there is a stator B1 and B2, with one of them going to that 2.5-ohm resistor and B2 from the ground tab. I think this is where i'm supposed to be checking voltage for that first few seconds it runs, but i'm not sure.

Ok, so it must be closing a relay. I couldn't find that in the diagram but then again the diagram leaves a lot to the imagination. Can't help with the generator side of things.

I never figured out the b1-b2 business, but I pulled the brushes and cleaned the slip rings just to see - and it took off and ran.
no-load voltage was like 190 or so though, so I've got to get that toned down before I can actually use it
baby steps


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