Onan 7.5DKDFJ Generator Fuel Shut Off Solenoid

Rich Biebel · 08-10-2016, 01:35 PM

Solinoid has a "pull" coil and a "hold" coil circuit....if it has 3 terminals on the solenoid.

One terminal is pull, one is hold and the other is common or ground.....

The pull coil gets energized during cranking. Drops out and hold coil keeps it energized once it's running and generating ouptput.

The higher voltage you see running is charging voltage....they have alternators....usually a little one like a Shogun....with a separate V/R-rectifier

Might just be a bad solenoid. Or possibly a control issue.

If it stays in once it's running the hold circuit is good.

I would use a voltmeter to see if the "pull" side of the solenoid is getting voltage during cranking.....

If it is the solenoid is bad.....
If it isn't the pull circuit has to be diagnosed.
A print from a Service Manual will be needed....

You could use a jumper and hit the terminal NOT energized when it's running on the solenoid with 12+ to see if it pulls in as long as the negative or common is connected to B-

A Fluke Voltmeter shows you DC polarity.......when something is energized.....I use it all the time to ID DC circuits that way....

08-10-2016, 01:35 PM	#2
Rich Biebel VIP Member Join Date: Jun 2007 Location: Northern New Jersey suburbs Posts: 2,320 Likes: 25 Liked 557 Times in 217 Posts	Re: Onan 7.5DKDFJ Generator Fuel Shut Off Solenoid Solinoid has a "pull" coil and a "hold" coil circuit....if it has 3 terminals on the solenoid. One terminal is pull, one is hold and the other is common or ground..... The pull coil gets energized during cranking. Drops out and hold coil keeps it energized once it's running and generating ouptput. The higher voltage you see running is charging voltage....they have alternators....usually a little one like a Shogun....with a separate V/R-rectifier Might just be a bad solenoid. Or possibly a control issue. If it stays in once it's running the hold circuit is good. I would use a voltmeter to see if the "pull" side of the solenoid is getting voltage during cranking..... If it is the solenoid is bad..... If it isn't the pull circuit has to be diagnosed. A print from a Service Manual will be needed.... You could use a jumper and hit the terminal NOT energized when it's running on the solenoid with 12+ to see if it pulls in as long as the negative or common is connected to B- A Fluke Voltmeter shows you DC polarity.......when something is energized.....I use it all the time to ID DC circuits that way.... __________________ Rich Biebel S/C 1479 Stock 147R Last edited by Rich Biebel; 08-10-2016 at 01:39 PM.