Community Forums

tom41 · 06-13-2015, 05:00 AM

Last week with the information from guys here I was able to get the starter off of my generator. It was a 30 minute job without having to remove the gen set from my motorhome. There is a metal plate on the backside of the housing that the generator sets in. and the starter is right there and easy to

remove. I ordered a new starter from DB Electrical and received it the following day!! Fast service! Ok, now I have the new starter installed and it turns the gen set over just fine. Now here is where I need some more advised and information (in other words, HELP!) the gen set starts but will only keep running with the start button held down. It has been about a year since the generator was run, because of the bad starter. Has anyone had this type of problem and if so what was the cause and where do I start checking out. Seems I read sometime ago about this problem but now I can't find it. thanks for any help and info on this problem

tom41 · 06-13-2015, 05:04 PM

I checked the oil pressure switch and it checked out ok, Gas is getting to carb ok, I understand that since the gen set will start and run while holding the switch down that the Voltage regulator would be ok. Looks like I will have to take it to the shop.

Americanrascal · 06-14-2015, 03:17 AM

I really scratched my head on this but can't think of anything. Please keep us posted on how this works out.

tom41 · 06-14-2015, 05:03 AM

thanks Rascal, I will keep an update on how it turns out. When the starter went out last fall, the generator was operating like it should. In the meantime I will keep checking things out. I really don't need a generator but I just like for everything to be operating as it should. thanks again

Percival6 · 06-17-2015, 10:19 AM

I am no expert at this, but I would have to say that in a year the gas has probably gone bad. How long have u run it? Was it enough time to get fresh gas into the carburetor? I have read about varnishes forming on the carb surfaces, that may be a factor too. Hopefully someone with more experience will chime in and give you more answers. Good luck! Tom

tom41 · 06-17-2015, 03:38 PM

Thanks Percival6 , you may be right about the gas. I have used the motorhome several times and of course the gas in the tank is fresh, but as you said the generator has not been run because of the starter being bad. Last year the old starter was locked and I turn the gen-set with a hex wrench and it started up but I had to keep working the gas lever and the attitude adjustment on bottom of carb and finally got it running good and would run everything in the coach. then in a month the starter locked up again. I just put on a new starter last week, and it will start like it should but will only keep running with the start button held down. I just hate to have to pay $100.00 an hour to someone when it can be something that I can fix. thanks again

Percival6 · 06-17-2015, 08:58 PM

That's weird, it only runs when you hold down the switch? So, as soon as you let it go, the engine immediately dies? That sounds more like an electrical problem. Like the fuel pump isn't staying connected. Or maybe the stop circuit/switch is engaging and killing the engine. Just throwing ideas out there.

tom41 · 06-18-2015, 03:44 AM

yep it is mind boggling no doubt about it. What is confusing is that last year before the starter froze up, the onan was working and powering everything in the coach! This is the 3rd motorhome I have had with the onan, and so far all 3 have gave problems. I am beginning to believe that onan generators are very unreliable. I had problems with everyone of them and they are not cheap to have work done on them. But I will keep on this one until it does work! lol

tom41 · 06-20-2015, 12:03 PM

I checked the oil pressure switch and it checked out ok, I don't really know how to check the voltage regulator or the mother board. I plugged in the power cord to generator and it does not produce AC to the coach even while holding the start button down and generator running... I'm about as far as my limited know how will get me unless some of you guys have any suggestions. Dang I sure do hate to give up but I don't want to do something to make it worst.

tom41 · 06-20-2015, 04:42 PM

Update on Onan...After taking the board out and examining it, and the start switch, I found nothing but I now suspect the start switch on the generator. I went inside and pushed the start switch on side of kitchen counter and it STARTED and RAN!!! until I went outside and cut it off with the switch on Onan. Then it wouldn't start and stay running with holding down switch. It smell like it might be flooding (I had put in two bottles of gas treatment just in case I got it running) Well I waited around 10 minutes and went back inside and pushed the inside start switch. It started and kept running without any holding down of the switch. I let it warm up for 15 minutes and plugged the cord into the box for the coach and now everything is powered including microwave , fridge, tv, and everything on 110. I will let it run for another 30 minutes then turn the roof air on. I think I will let it run for a couple of hours since it has not been run for a year because of the frozen starter I have just installed a week ago. I thank the Good Lord for guiding me and giving me the courage to venture where I knew nothing!! And thanks to everyone who posted back and all their advise and suggestions. I believe someone said that it could be the switch and now I think so to, but the switch is made (soldered) onto the mother board. thanks again everyone

Americanrascal · 06-20-2015, 05:18 PM

Tom I am wondering if you on to something using the inside panel start vs outside switch. On the newer Onan 4000, if attempting start from the outside on the generator, one must hold the outside "STOP" switch for a required priming cycle for a good bit, the light then flashes. Then it will fire and operate from the start side of the switch once fuel has adequately moved to the generator.

I don't understand the difference in the starting requirements inside vs outside but that's how ours operates.The inside switch we only must hold the switch until it starts- no required priming cycle. I wonder if that's associated with your problem?

Percival6 · 06-20-2015, 07:42 PM

Ours is a 2009 or 2010 vintage Onan 4000, the inside switch functions just like the outside. I can hold it to the stop position and it primes the engine. Then press start and it will fire right up.

Glad to hear that it has started AND kept running AND it makes electricity. At least it's the outside switch thats the problem and not the inside one. It would suck if you had to go outside every time to fire it up!

Sometimes just dumb luck and perseverance are all that's needed to figure something out that makes no sense what so ever.