genset runs only with button depressed

Ya the 4000 will not fit out the door, it looks like it drops to the ground so I will try that.

If you're still looking for tips on removing it from the MH, here's one, maybe... My 2800 is bigger (wider and taller) than the compartment door opening. I found that I had to remove the door and door frame. Peel the rubber trim out of the channel around the door frame to get to the screws. Still a PITA, but doable now.

(on edit) While it's out, and if you'll still have air circulation space around it, put some foil-faced rigid fiberglass insulation on the compartment walls, and make some big rubber washers for the mounting bolts (between gen pan and frame); use blue Loctite and longer bolts, tightened just snug. See the Onan installation manual for details on required clearances. Most MoHo builders cheap-out on generator installation, resulting in a noiser-than-necessary product.

Jim, "Why are there never any _guilty_ bystanders?"

Questions,
Has the genset been sitting for a while ?.
Has the genset been shut down under load many times ?.

The genset has to produce AC first, before the ignition system of the engine will keep on producing ignition, so when pressing the start button, your by passing that function until you release the start button.
Normally it could be the brushes not making contact or the gen part failed & if the genset has been shut down under load several times, it could be the regulator messed up & needs replacing.
Either way, what evers wrong, contact "Flight Systems" for questions or repair parts, because they will be way cheaper than going the Onan parts or repair route.
The Flight Systems replacement regulator, is rebuildable, where as the Onan you got to replace completely.
Neil

If you unplug the regulator. There will be no AC out put. Plug it back in. Get a volt meter and do some test. Make sure you have no output before you spend any money. Also look at the oil pan. If it has a wire going to it. Unplug it. That is the low oil level sensor. The early models had them. But they caused so many problems Onan got rid of them. Get the service manual it will have all the test you need.Easy to check things out.If you will post the full model and serial number. The guys on smokstak. Can send you a manual.

I will remove it and fix it myself , I was just looking for direction on removing it from the motor home.
I run a small engine / snowmobile engine shop so motor wise I'm good but it just looks like some tricks to removing it from the motor home and thought someone may have some insight to doing this.

Thanks

Getting at the brushes on a 4000 microlite is a job best left to an ONAN tech. As a beginning, please obtain a "service" manual. It contains not only the troubleshooting but also the mechanical steps necessary to get at and/or replace the brushes (they are under the flywheel). If you cannot get a manual, please take pictures during disassembly so you can put it back together later.

JimL

Mine did that. $2350 later fixed by onan factory dealer. Bad stator, rotor and
regulator. They cost over $4000 to replace.
Had no choice. Has to come out and all apart. Could be any or all of those things.
Bob

Does not matter which button I use.

Mine does the same thing. I took it to the Onan shop and they said the windings were bad and I needed a new genny. I don't believe them.

There should be a start button right by the generator. I don't know which button you are using (a remote start button in the "B" or the one on the generator itself.) Same thing happen if you use that?