Cummins Onan Generator Starting Issues - Help Needed!

[trigon]

Our C.O. generator in our 2018 Forest River Stealth toyhauler only starts "occasionally". This started happening last December. It has been in storage since the pandemic started. I've gone out every month to exercise it, sometimes it fires right up, other times nothing. What I mean by nothing, is no cranking, no fault code, nothing. I should say nothing now, the very first time this happened was in the early evening in a campground with no hookups. I hit the start toggle and the lights in the kitchen area dimmed. I stopped trying to start it immediately, and not knowing what to do went and checked the Go Power Solar display, and it was going crazy flipping through screens. It did start right up the next morning, but the lights dimming during a failed startup only happened a couple more times. Since then, if it fails we're back to nothing, except for the Solar display flipping out, aka "error mode".
"Finally", after waiting months, it is in the shop being looked at, when I talked to the service manager about it yesterday, he said "it fired right up, each time they tried". I begged them to please keep it in the shop a few more days, and keep starting it, until it doesn't, then figure out why it isn't. What i'm afraid of is this issue will not get resolved, and then we take it out boondocking and it won't start. And then we are back to square one again.
We would be so grateful to any RV owners who have had this same experience, or any RV techs with experience on this issue, that can give us feedback on what the cause and solution to this could possibly be, it will be greatly appreciated! Thank you for all helpful replies!

[dbutton]

Search Onan fuel pumps. I have read that the electric their fuel pumps don't last.
If it was mine I would just replace the fuel pump. Electric fuel pumps on anything are problematic.

[spicercars]

I have had three onan fuel pumps in mine the first two years at $100 plus every time. The forth time I went to napa and bought a low pressure electric one and used that for many years without any problems. I also installed a good inline filter before the pump.

[Lins]

compare how you and the shop are priming it (or not) before starting.

[trigon]

Thank you for your replies. Being as there is no generator response at all, and no fault codes when not starting, wouldn't that eliminate it being a fuel pump, or priming issue?

With those issues, you would think the generator would at least turn over. Your thoughts?

[Lins]

I missed the no crank part. Sounds like you run the battery too low. Is your solar providing a charge at all? If it is, have the battery load tested to make sure it’s still ok.

[Thomas ho]

Repair shop probably had shore power plugged in. If you are depending on the battery it is probably bad , low on charge . Solar only can do so much for charging up battery.

[trigon]

Lins & Thomas ho - A couple months ago I checked the two AGM 6v batteries. They read 6.77 and 6.79 volts, indicating a good state of charge, I think? But, i'm not sure how that reflects their CCA capacity. I guess, as you suggested a load test will be the only way to really know the strength/health of the batteries.

The Go Power Solar Controller display, read 100% charge at 13.7 volts, at about the same time I checked the batteries.

I will talk to the Service manager today about whether the trailer was plugged in when they started the generator. And request a load test on the batteries, as well as servicing them, including checking the ground and positive connection.

Thank you for your input!

[aircommuter]

You need to take voltage readings at the starter when this happens and work from there.

[Nomore9-5]

Originally Posted by trigon

Our C.O. generator in our 2018 Forest River Stealth toyhauler only starts "occasionally". This started happening last December. It has been in storage since the pandemic started. I've gone out every month to exercise it, sometimes it fires right up, other times nothing. What I mean by nothing, is no cranking, no fault code, nothing. I should say nothing now, the very first time this happened was in the early evening in a campground with no hookups. I hit the start toggle and the lights in the kitchen area dimmed. I stopped trying to start it immediately, and not knowing what to do went and checked the Go Power Solar display, and it was going crazy flipping through screens. It did start right up the next morning, but the lights dimming during a failed startup only happened a couple more times. Since then, if it fails we're back to nothing, except for the Solar display flipping out, aka "error mode".

"Finally", after waiting months, it is in the shop being looked at, when I talked to the service manager about it yesterday, he said "it fired right up, each time they tried". I begged them to please keep it in the shop a few more days, and keep starting it, until it doesn't, then figure out why it isn't. What i'm afraid of is this issue will not get resolved, and then we take it out boondocking and it won't start. And then we are back to square one again.

We would be so grateful to any RV owners who have had this same experience, or any RV techs with experience on this issue, that can give us feedback on what the cause and solution to this could possibly be, it will be greatly appreciated! Thank you for all helpful replies!

To me the most significant thing you said was you lights dimmed which is a sign that there wasn't sufficient juice to start. Not sure if your solar system is producing enough to stay ahead of what your needs are or the batteries are the issue.