Onan voltage regulater

[Hacksaw]

I also have used ASAP / Parts for Techs. Good service and reasonably priced.

[ss3011]

Wide range of prices, but there is one on eBay for $222.00 . There is a good set of instructions that I saw when I Googled that part number , to test the old one to make sure its bad . Doesn't look like a very robust connector , might try cleaning it good and retrying it . Good luck !

[rseibenick]

Yes its a Marquis 111. will try cleaning the contacts first and see.

[Rich Biebel]

Won't help. It's never been an issue. First thing to check on those is always brushes, and slip rings. The brushes ride on those slip rings. Copper surfaces on the rotor. A normal ohm reading right at the back of the brushes with at least one wire pulled off........about 20-30 ohms. If brushes and slips are good you can pull wires off brushes, tape them up and connect a 12volt battery or better yet a 24 volt supply right on there and run it. Output should be produced although it will be low. That test will be proving the rotor and stator are good. 30 to 60 volts D.C. is the normal range there. Marquis' are complex units with electronic governors. Harder to diagnose than manual governors. Pretty easy for me though.

[rseibenick]

Rich, had the unit checked out and they said it was a bad voltage regulator. Slip rings and brushes good. Will try to clean the connectors and try that if not will change out the regulator.

[MIRADA]

The regulator is available thru your nearest cummins dealer
Not sure how much they are in the states , but they are $875 Canadian
And are a week or so away if that helps , I work for a Peterbilt dealer
And we can get them from Memphis warehouse...

[voltdr]

The one from flight systems is $245.00

[Rich Biebel]

The Onan part is $413 list price...

You would be very lucky to find anyone selling it for much under list....

If the unit was diagnosed as having a bad VR your options are either an Onan or one from Flight or ASAP and ASAP sells both for some machines.....

I am and our facility is an ONAN authorized repair facility.....20+ years....


I have and use a G-Man generator tester as well as a variable voltage power supply to diagnose these machines.

The G-Man is a breakout box and is good but it cannot substitute for a "known good" Voltage regulator......

I always confirm all other components are ok before plugging in a new VR....

[rseibenick]

Rich, the tech. plugged in another regulator and it worked., had ac power .It was not the exact right one , but he said it should tell me if mine was bad. He said I should get the exact one Onan had for that generator.