Generator help please

[Bryan Quinn]

Hello all.

Wondering if some can help with a generator issue I am experiencing on my '98 Contessa. The generator is an Onan Marquis 6500 LP, with 475 hours.  The generator starts and runs just fine, but I have to turn it off & restart it 2 or 3 times before power will be supplied to the coach.  Today it took 5 on/off cycles.  Any help/direction/advice would be greatly appreciated.  I'm in the middle of a 3 week vacation with it.

Bryan

[Steve Huber Co-Admin]

Bryan,
First check to see that the black toggle switch on the front panel of the generator is in the ON position. If not, geni will run but no output. I'd flip it back and forth a few times (w/geni off) as the switch may be dirty, etc. If that isn't it, I'd check the transfer relay next. It switches between shore and generator power. Mine is located in the geni bay (I have rear generator). Good thread on this topic is:
"Onan 7.5 KV Diesel Generator, Model HDKAJ"
Steve

[Edward Buker]

I had an Onan 6500LP and this seemed to be a common issue if it was shut down for extended lengths of time. My conclusion after a lot of looking was that this was a self exciting field on the generator and it needed a certain amount of residual magnetism to generate enough of a field to get things started. I may be off on this, but after several tries, it never seemed to fail to work, but it was frustrating. If it is this symptom, it will shut itself down and you had to hold the starter on for an extended length of time until the excitation was adequate to have it start self generating.

Info, that this is a self exciting design used by Onan in the 6500

http://campkahler.com/files/onan/emerald6500.pdf

If could also be what Steve has indicated as issues.

Later Ed