Hello, this is my first post so I hope I don't commit any breaches of etiquette. I have a 1991 Southwind motorhome with an Onan Marquis 7000 generator I am trying to troubleshoot. I have a friend who is an electronics technician and can probably diagnose my problem with the proper information. Does anyone know where I can download the service manual for my generator? The model number is 7NHMFA26106B (B=specB) and the serial number is G910403803. Even the correct number for the Onan service manual for this unit would be appreciated. I found a downloadable service manual for a Marquis 7000 NHM but it was for the spec J model which is different from mine.

• Onan Marquis 7000 Parts Manual
• Onan Marquis 7000 Generator Service Manual

I believe my problem lies either in the governor or the control panel which sends signals to the governor and this is the area where my spec B is different than the spec J I found. Thanks for any help Richard.

Hello, I'm looking for the parts,and service manuals for my onan marquis 7000 generator. Serial # L900363626 Model# 7NHMFR26106B I also have a couple problems I was hoping you guys could address. There is gas in the oil. At first I thought it was bad rings and it would need a rebuild, but hopefully it is carb or fuel pump related? At first I thought it was really old oil so I put in new oil and ran it for several hours one day. It worked great.

The next day I ran it again but it stopped while I was using it. I checked the oil and it was black and thin. Smelled like gas. I tried to restart it but the F1 fuse was blown. I blew five standard fuses ( not slow blow) after that.

While trying to start it would turn over about 3 times then blow the standard (non slow blow fuse). What do you guys think? Do I need a new control board? New fuel pump?

The generator is in another state, and I dont have access to it, so this is kind of a theoretical excercise until I get back there to work on it. Thanks for the help. When it did run was it throwing out black smoke, (running too rich)? I also have 7NHM. Yours was built in Dec of 1990 and it's spec # is B Has factory electric gas pump. If gas tank is above gen gas can siphon thru carb if float valve leaks. If gas tank gets pressurized from being hot and that might make gas flow if float valve leaks too If my gen sits for few months gas in carb bowl dries up and float drops down.

Sometimes it jams and doesn't shut off gas flow. But when mine does that gas leaks out of carb directly onto ground when pump is running. Tapping carb with small wrench frees it up.

Manual numbers and link to them. BGM-NHM-SERVICE-965-0531B NHM- SPEC a-h -(9-98)-PARTS 940-0230 BGM-NHM-INSTALL-(5-92)-965-0631 BGM-NHM-OPERATOR-(3-93)-965-0131 Schematic for your gen is on page B-3 of service manual ( at end) F1 blowing.Could try a slow blow fuse as it calls for.

Reg fuse might respond to pulses from gas pump. Look over control board for any obvious signs of burns or shorts.

I'ld guess some powered wiring coming out of control board is shorting to ground. Check wires for shorts and abrasions, also unplug remote switch at the gen to isolate any shorts in remote wiring. Explain something master Yoda will. Don't spend any money until you have read the manual and understand the test. Do the test first to prove an item is bad. Both spark plugs fire at the same time. It will run on one and will carry part of a load.

Trash in the carb will also cause gas in the oil. Ask any question you need to. We have a very good team of people here. Always willing to help. Even us cranky old farts Welcome to the stak. Thanks, I am here to learn. Looks like I found the right place and the right people.

Onan Marquis 7000 Parts Manual

Yeah it will take me a bit to digest those manuals. Not buying parts I dont need is the goal.

Not wasting time with a lost cause is also. No black smoke while it was running. Remove the gas cap to depressurize the system I assume? Yes Ive read that if the fuel pump diaphram is bad it could leak into the crank case? That's for mechanicaly driven pumps mounted on engine block, if their diaphragm leaks fuel can drip thru block into oilpan. Your is electric so not attached to block, so no drip path into oil. But if carb float is stuck gas can leak thru carb into intake then down to oil i was using a skill saw when it happened.

Onan Marquis 7000 Generator Service Manual

The genny was reving down and i started the skill saw and instead of revving up again like before it just stopped. So maybe it was too much draw at the wrong time that that blew the fuse? Governer on this gen is electronic, think it uses a bit of current, could be the normal fuse you used responded to the brief increase in current demand. Try a slow blow fuse as it calls for.