Onan 4000 Generator Not Cranking

[fitzzy]

The solenoid has 12v on one side and when cranking it only allows 7 v to go through. When you jump the solenoid it still does the same thing, It does not crank it. There is just a clicking sound and generator worked just a week ago. The batteries are good, but may not be fully charged. We have had plugged into shore power for about 8 hours or so today. Hubby had turned the batteries to off while on our camping trip this week so this could be it too. Never had a problem until now. It's a 2013 3170DS Sunseeker we purchased used earlier this year.

[bubbles]

If your coach has an emergency start function you could engage that switch to see if the genny will crank. If so that would be an indication of low charge coach batteries. Emergency start ties the coach and chassis batteries together.

[cavie]

Originally Posted by fitzzy

The solenoid has 12v on one side and when cranking it only allows 7 v to go through. When you jump the solenoid it still does the same thing, It does not crank it. There is just a clicking sound and generator worked just a week ago. The batteries are good, but may not be fully charged. We have had plugged into shore power for about 8 hours or so today. Hubby had turned the batteries to off while on our camping trip this week so this could be it too. Never had a problem until now. It's a 2013 3170DS Sunseeker we purchased used earlier this year.

It's only allowing 7 volts to go thru because that's all you have. The batteries are not good. They are dead. Disconnect and give them a good slow charge. You need at least 12.6 volts.

[fitzzy]

Thanks! I keep saying I don't think the batteries are charged. Do you mean the house battery? What are you referring to when you say disconnect? Sorry, so many questions just want to be sure I am relaying the message correctly.

[cavie]

Originally Posted by fitzzy

Thanks! I keep saying I don't think the batteries are charged. Do you mean the house battery? What are you referring to when you say disconnect? Sorry, so many questions just want to be sure I am relaying the message correctly.

Disconnect = remove the cables. The battery that starts the generator. I'm assuming it is the house battery.

[JLeising]

A previous poster (couple of years ago, I think) had a similar problem. Determined his battery was good. Eventually found a corroded ground wire at the generator, as I remember.
If you connect a voltmeter to your house batteries (I believe the generator starter works off the house batteries) and another to the generator solenoid (alligator clips work well) and monitor both voltmeters when you try to start the generator, you can isolate the problem. If the battery voltage stays relatively high (over say 11.5 volts) but the solenoid voltage drops a lot (7 volts?) the problem is in the wiring. If the battery voltage drops precipitously, bad battery or battery terminal connection.
The previous poster actually found he could start his generator by using a separate jumper battery and jumping directly to the starter and the solenoid, as I remember.

[lucky55616]

Try starting the engine, the battery control center should allow enough current from the engine alternator to the house batteries to give you the extra voltage you need to get the generator started. This has worked well for me in the past, I did not even need to use emergency boost switch.

[cavie]

you can't do anything until you verify 12.6 volts at the battery

[Garrette]

Start the truck and let it idle for a bit, than give it a go. Does sound like weak house batteries. Can you run a slide (couch slide) out? If so, not the batteries.
Let us know what you find.

[Cold Lake Kid]

I had the same problem with my new house batteries doing the same thing.
As recommended by Lucky and Garrette, I simply start the truck engine and then try the generator. Once the gennie is going, I shut off the truck engine,
Mind you, I also carry a Honda 2000 as back-up.

[fitzzy]

We found it was a ground wire that had disintegrated. Once that was replaced, it worked! Not an easy thing to get to, but a cheap fix.