Anyone familiar with Onan gensets?

[stephen4785]

Iv got one on a trailer that wont stay running. if you hold the start switch in the start position it will run but soon as you let go it dies.
Any ideas?
Onan 7.0hgjab spec D

[SMKR]

Have you checked the points?

[stephen4785]

Have you checked the points?

No, I dont know crap about generators. The oil level sensor was replaced and a mechanic took off the carb for some reason but thats all I know.

[SMKR]

let me look through my old notes, we had an onan generator that we worked on constantly for 6 years on our old 76 motorhome.

[SMKR]

here is a good reference:

http://www.flightsystems.com/pdf/onanrvtshootgd608.pdf

[SMKR]

how old is it? Older gen probably needs some basic tune up -- spark plugs, fuel filter, air filter -- and carb is probably gummed up (clean it - sometimes running fuel withSeaFoam will be sufficient to clear out gunk). Run some SeaFoam through the system, by disconnecting the fuel hose between the fuel filter and the gas tank, and then getting a section of hose to draw the gas up out of a separate container with the SeaFoam mix in it.Run it for about a half-hour, and you should see some improvement. I would then replace the fuel filter, spark plug and the air filter, as well as do an oil change.

[ram57ta]

getting past the fact that its a generator....look at it like its a lawnmower engine. Take the carb off and HEAVILY clean it....all the jets, the float, clean or replace the air filter. Replace the spark plug. Pull off the plug, ground it and spin the engine over. If you get a nice strong spark you can assume the ignition is good although it still might be a good idea to replace the points/condenser (unless it uses electronic ignition). Does it have good compression? I've fixed several generators that basically were used a couple times and then left sitting for years with gas still in them...which is one of the worst things you can do to a generator. I have a 6000w coleman now that I paid 80 bucks for...it was bought and used ONCE and then left sitting. It looked brand new when I got it...but the carb was one of the worst I've ever seen. It runs like new now.

[Strychnine]

Cummins Southern Plains / Onan tech support.
For the small stuff like that call Bill Bundy. (817)640-6884. You'll probably have to leave a msg, the phone support guys get blown up all day long.

[stephen4785]

I figured it out. The brushes ontop of the generator are messed up. One of them is melted into the plastic holder. It would start and run fine until you released the start button. I checked voltage from the field brushes and didnt get an a/c voltage. Pulled the assembly out and the slinger rings were carboned up really bad. High resistance equals high heat and melted the plastic holder that holds the brushes.
Thanks

[JimD]

No signal from oil level switch will cause it, rule that out first. Then check voltage reg for output voltage, won't run if its not producing electricity. Ive got manuals for BGE/NHE but not that.
Cool website for help, post up there they will fix ya up.. http://www.smokstak.com/

[Sean88gt]

I don't, but the Onan guy is above my office.

[Nash B.]

I don't, but the Onan guy is above my office.

Scoreboard.

[Sean88gt]

scoreboard.

lmao!

[Strychnine]

lmao!

Scoreboard this

[Sean88gt]

Oil field manager/drilling? Looks Texan to me