Onan Generator Won't Run

[NevadaM]

I have an Onan generator that was once in an RV and is operating on Propane. Model 6.5 NH-3CR/16000A. The issue is it won't keep running. When the start button is pushed, it cranks over and fires a couple of times, then fuse F2 (IGN) blows and when the start button is released it stops cranking. I am using Onan Control drawing 611-1135 dated 4-8-77. At first it was thought the seal-in relays K2 and K3 were sticking in the open position, but both have been replaced. Then looked at the Diode CR1. When I checked CR1 with the diode test fxn on my multi meter, it appeared to be open both ways. I replaced CR1 with a new diode although it also checked open both ways (no tone). Can you enlighten me on how to check a diode like this one, it is obviously different than the standard .7 volt diode. Regardless, I'm quickly running out of thoughts, looking at the schematic on the drawing, I see there is a C1 that might be shorted or could the points S2 be causing the fuse F2 to blow? Something is shorting out causing an over current through F2 and I can't find it. The start Solenoid K1 must be working as the generator is cranking over as long as the start button is held in. Again, it only fires a couple of times, then that must be when F2 blows and it quits firing (makes sense because no more current to the points and plugs). The only other thing I see in the circuit is S3 the low oil pressure switch, but the oil level checks fine.

Can somebody shed some light on why this fuse is blowing?

Thanks, Steve

[ammdrew]

On the gas version that is usually a fuel pump failure or the control board that causes the fuse to blow as soon as you release the start button.

[cadman99]

Read this

http://www.flightsystems.com/pdf/ona...oing-guide.pdf