Onan stop solenoid not getting power

[Guilhem]

Hello, My 6kW Onan generator won't start. This is what I found:
- if I manually pull on the spring-loaded lever that the stop solenoid is supposed to pull when energized, then I can start the generator and it runs fine.
- if I disconnect the stop solenoid, and temporarily apply 12V to its connectors using wires and a spare battery, it operates correctly, that is, it pulls the lever with a "clunk" noise as expected.
- if I run the generator (manually holding the lever) and check voltage on the wires feeding into the solenoid, I don't get 12V - even though I understand I should.
So looks to me that the solenoid is working properly, but not getting the signal to do so.
Accessing the control panel, disassembling it and poking around on the circuit board behind it is very difficult due to its position in the boat and the stuff that blocks access to it, which has to be removed before a bit of boat yoga allows me to even see the damned panel. So before I do so, I would like to poll the audience here for possible causes. Fried relay on the circuit board? Corroded wire or connector? Any other idea?


Thanks

 

[Lepke]

Relay could be separate from the board.

You need the schematic and trace power from the stop solenoid back to the board.

 

[Simi 60]

Just did this on ours
Moved relay from switch panel down to genset
Increased wire size
All good again, better than its ever been.

Only taken 6 years to get it sorted
Clearly Genset is low on my priority list.

 

[Russell Clifton]

A dock neighbor just had this exact same issue on his Onan. Turned out to be a circuit breaker had tripped. The breaker was located on the control panel located on the generator.

 

[High Wire]

Could be a bad sensor. High exhaust temperature switches seem to go first. Your best bet is to break out the wiring diagram and find where the +12VDC goes away.

 

[Guilhem]

Thanks for the recommendations. Looks like I need to get all the way in the back of the engine room to the control panel, which requires me to remove some other parts that are in the way and prevent access. This is going to require more time than I thought initially... Will keep you posted of what I find out.

 

[Alaskan Sea-Duction]

Following

 

[Barking Sands]

do you have a wire diagram handy? Post it here? Maybe even a model number so we can search for the diagram?

 

[hmason]

It could also be a weak generator start battery or a failing alternator on the generator.

 

[hmason]

Help, my avatar is headed north! I hope a mod can fix it. Thanks

 

[Guilhem]

All right, problem solved. It was a combination of two things. 1/ me being stupid, using a new multimeter, with the + wire plugged into the Amp port, not the Volt port, so it was showing 0 all the time... Should have tested this straight on the battery. There *was* power at the end of the wires that feed the stop solenoid... 2/ the connector at the end of those wires had gotten loose, but since I had removed it to test with the multimeter, I didn't notice. Re tighten it, reconnected properly, and here we go, the generator works fine now...
Thanks for your help, this one was cheap in the end, but took me some time to figure out. At least I know my system better now ;-p !

 

[Barking Sands]

LOL...I have done that a few times in the past. These days when all voltages read 0 you definitely check it on a known good power source. Glad you got it solved...and solved yourself without calling anyone out. Same goes for ohms. When nothin ohms out right cross the probes and check for a solid continuity.