Onan Marquis 7000

[drcausey]

I have an older 1994 Onan Marquis 7000 genset in my motor home. Today I replaced the engine and coach batteries, partly because my generator wouldn't crank and partly because they are four years old!! The generator still won't crank!! I have checked ALL the battery cables and the grounding cables. Could the starter be bad?

[nukerj]

Could be several issues:
ensure that you have the disconnect switches for the coach and chassis batteries turned on so that you have power, you can check this at the generator with a multimeter.

Then check to see if the generator starts from it's own control panel instead of the remote panel if you haven't already done so.

If you have 12v at generator, check for 12v at the gen starter during start procedure, if you never get 12v at the starter then you could have a bad switch, relay or control board. So work backwards from the starter checking for 12v at each of these components.

That is the simplest method of tracking down an electrical issue.

[ScottyBye]

Originally Posted by nukerj

Could be several issues:
ensure that you have the disconnect switches for the coach and chassis batteries turned on so that you have power, you can check this at the generator with a multimeter.

Then check to see if the generator starts from it's own control panel instead of the remote panel if you haven't already done so.

If you have 12v at generator, check for 12v at the gen starter during start procedure, if you never get 12v at the starter then you could have a bad switch, relay or control board. So work backwards from the starter checking for 12v at each of these components.

That is the simplest method of tracking down an electrical issue.

Yes to all nukerj said.
And here is a link to Print or Save digital for future reference.

https://www.flightsystems.com/pdf/on...oing-guide.pdf

And I would check the control fuse(s) I think on that model they are located on the right side of the control box (external) but I can't be sure...