This past week at Pismo we were having Generator problems, we've never had before. We are in a 1996 Moho and the generator will turnover and start but as soon as you let go of the button it turns off. Any ideas? Husband is hoping it's just the switch and will probably get a new one this weekend but has this ever happened to you or have any ideas what it is. Thanks,
Shelly

Oil Pressure/ Oil level switch is probably bad. The start switch bypasses all the "safeties" and allows the engine to continue to run while the oil pressure is coming up.

or its low on oil. try adding more oil to it and see if that works.

The oil I belive he checked it and the levels were okay but i will be telling himm just in case
thanks any ideas help

i will let him know to check that out topo! thanks,

1 qt low could cause the problem

Some MH's have a fuel level safety on them. If you fuel tank is 1/4 or less, the will not come/stay on. Also, if you have a diesel gen. and is water cooled, the coolant level may be low.

Frank

I bet its the carb is gummed up that happened on our old m/h

Check oil, the low fuel level has caught a few people by surprise. If that doesn't work, hold down that start switch for about 30 seconds. You might get lucky and it will stay running. I just bought a lance camper with onan 25oo generator and it would start but die as soon as the switch was let go. It now works after holding the run switch for 30 seconds.

Ours did just exactly the same thing. There were tons of opinions, but in actuality, it just stopped doing it, and started working properly. It still will sometimes just die tho... the best one one I heard was the circuit board under the start switch on the gennie itself. This is a Onan Emerald 6.5 series in a '95 winnie

John

I had the exact same problem. 1999 Tiffin Allegro with an Onan 4000. It turned out to be the brushes. One set was completely gone and the other set only had about 1/4 left. Replaced them and have never had the problem again.

onan has a few safty features that will shut the motor down. oil will do it, the other is if it not charging when started it will shut down. that will lead you to the voltage regulator, brushes or a ground in the windings. i feel like i know more than the guys trying to fix my onan 4000 right now. thay have had it for 2 weeks and still cant figure it out. i am picking it up tomorrow morning, if it is not running yet i will spill the beans on the crappy shop so i cant happen to others.

I have a 200 page onan service manual also if anyone need me to check on a problem, it has a pretty good diagnostic chart

My 91 Jayco w/ a Onan Genset 4000 had the same issue. Getting information from Onan dealers is tough in my area. They want the Service $$$. I found a web-site that sells Onan replacement parts, specifically the circut-boards. When I spoke to their tech he walked me through some tests for each safety control. Then he concluded it was the circut board. $175 bucks later is was running good. The same Onan boards were around $280, and if that's not your problem Onan will not take the board back. This guy at Flightsystems told me if this didn't fix it he would refund me. I took him on his word and it fixed the problem. Apparently the unit starts and then checks for system voltage and if alls good keeps running.

If you need to check into this I'm putting the link here for you. http://www.flightsystems.com/

Did you get ot fixed yet? I'll bet it was not the switch?

richardsrv

Could be the belt... I had a similar issue as well as my friends with Onans.. After about 1000 hours, the belt that goes to the water pump fails.. The generator will run for a minute and then shut off.. If you remove the inspection cover on the bottom, you should be able to see the belt or peices of it if this is the problem.

One of my friends Onan Generator wouldn't keep running.. They found out it the floats were stuck...

My Onan is doing the same thing after this weekend. It will run only if the start button is held down...but once it is released the thing dies! Checked the oil, full...only has about 180 hours on it..It was running fine then just died.

Any help?

We fixed our generator. Ours was the board on the generator. I guess it's the brain of the generator. Ours was doing the exact same thing as yours would only stay on when the button was held down but as soon as we released it would just sputter out and die. Hope that helps you.

Try putting fuel in it.

You'll need the service manual and a good multimeter with a diode check function. Any gen tech worth his own salt can troubleshoot it in an hour. What model is it?

Ill check which model tomorrow but i think it is the 5000. I can check the diode, were is it located?

The diode checker is to troubleshoot the voltage regulator. Newer models have it on the main board. It's location depends on the model. I'll need the entire model number, including the last letter. Other measurements need to be taken first, but the diode function may be needed. If you are mechanically minded, get the service manual, you'll need specific numbers in there. They're not all written well, I'll guide you through it.

If you haven't run it much (don't you have solar panels?) then the carb might be gummed up. There's a fuel shutoff solenoid that's incorporated into the main jet on most of them. It's what shuts off the gen when you hit the off button. If that gets gummed/clogged up, it won't stay open. I had an RV shop tell me the only solution was to buy the entire carb, since they don't sell the solenoid separately.

But I hooked it up to a portable jumper box and exercised it while shooting carb cleaner into it, that cleaned it up and it now works perfect.

[quote name='socaldmax' date='Jun 9 2008, 10:00 PM' post='2832663']
If you haven't run it much (don't you have solar panels?) then the carb might be gummed up. There's a fuel shutoff solenoid that's incorporated into the main jet on most of them. It's what shuts off the gen when you hit the off button. If that gets gummed/clogged up, it won't stay open. I had an RV shop tell me the only solution was to buy the entire carb, since they don't sell the solenoid separately.

But I hooked it up to a portable jumper box and exercised it while shooting carb cleaner into it, that cleaned it up and it now works perfect.


He said it was running fine and died and runs only with start switch pressed. If it has fuel and oil, the problem is electrical. The most common problem is the voltage regulator, now normally part of the controller. Other sensors may be to blame. It depends on the model.

I run the gen. about once a month with a load on it to keep that carb clean...I learned that the hard way with the last rig. I will check the model number today and get back to you. Thanks for all your help.

Ok I got the model number. Its a 6500.

That's the wattage rating. The model # is in a plate in the front, 8- 9 digits, Starts and ends with a letter.
Get the service manual or this will be impossible to do via email.

6.5NHEFA26100P MODEL NUMBER

any more help?

To prevent alot of common issues with gens it is cured by running that sucka for 30 mins to an hour once a month or so, its needs to run under a load like your AC on. It needs to do what its made for, WORK.

I was already worried about my gennie sitting too long, but I have been working too much to get down to the storage place to run it. So, with the added stress of this thread it got me down there over the weekend, for what i hoped was a quick drive-by to run the gennie a little. Of course, the batteries were dead, so I looked all over the trailer to find the jumpers to hook up to my car.

Anyway, the gennie would only turn over 1 "click" at a time. I don't think it was the battery, cause it was hooked up to the car with engine revved up. If I let off the start button and depressed again, I would get 1 "click" again. Over and over.

The gas was pretty low and it has been a good 6 weeks since the last start. If the carb was gummed up or it was out of gas, would it not at least continue to turn-over.

THoughts?

If any one looking for a great Onan repair shop, try Cummings Cal Pacific in Tustin Ca. 949-253-6000

I just got a 95 Southwind with a Onan 4000. It only has 220 hours on it. It has been sitting for 6-8 months or more since the last time it was ran. When I crank it over it won't fire. I sprayed some starting fluid in the carb and it fires and runs for a few seconds but then dies. I'm pretty sure this is some type of fuel issue but any ideas?

Thanks for the help!

DAN

Don't know if will help but. I have had similar generator problems, It has always come down to fuel delivery. For me most times it has come down to the float getting stuck in the carb. I do recommend taking it to a knowledgeable mechanic when you get home from your trip. I usually smack the carb. bowl a couple of times with a piece of wood or plastic if I'm having problems in the field. Works every time. Just call me primitive Pete.