Yes, I've pulled my generator. Had to take it out and put it back in twice in fact. I have an Onan 4BGE. My old 1990 Winnebago has it mounted on a "tilt out" frame, which has "hook" hinges that can be lifted off their mounts when keepers are removed. Then the entire unit lowers and pulls away from the RV. I used a cheap Harbor Freight dolly with some 4X4 lumber on top of it and a hydraulic jack. Others have used motorcycle jacks or transmission jacks.
I think that people who do RV repairs, and RV generator repairs, see RV owners as an easy mark. They tend to be older, and I think they figure if you have enough money to buy the toy you have enough money to pay to have it fixed. Plus labor is just super expensive today. When burger flippers get $10-$15 an hour, mechanics are going to make a lot more. I think it's hard to have anyone even
touch your generator for less than $500.
You will get a ton of expert advice on Onan generator work here:
https://www.smokstak.com/forum/forumdisplay.php?f=1
They will direct you to the service shop manuals for your generator that gives much more diagnostic and repair information than the owner's manual.
You may be able to work on the gennny in your RV, depending on how it is mounted. It can be hard to get to some parts of the genny. It's definitely easier to work on them out of the RV. Trying to get on your knees and contort yourself and work by feel is hard and it's harder when you're older like me.
But, the generators are pretty simple. First, there's the engine. It's pretty bullet proof as long as you don't run it out of oil. Second, there is the generator head. It is also pretty robust, and if it dies, you're pretty much looking at a new generator anyway unless you want to learn how to crack the genny in half and have someone re-wind the head. It can be done.
Things that give problems:
1) Carburetor. If you don't exercise your genny monthly and get fresh fuel running through it, and let it get agitated by heat and vibration from the running genny, you are asking for varnish and mold to build up in the thing. Especially with today's ethanol gas. You can forget about all the so-called "mechanic in a can" fixes like Seafoam or carb cleaner. They almost never work once the internal orifices are plugged up. Sometimes you can rebuild the carb if you are careful. Other times it's easier (or even recommended by Onan) to just replace it. It's about a $300 item.
2) Starter. I found an aftermarket one with a stronger design less prone to failure than my OEM one for about $30.
3) Ignition Coil. I found an aftermarket one for about $30 that included a new condenser as part of the kit.
4) Ignition Control Module. This I had to buy an Onan part. About $100.
So, I replaced my coil, ICM, starter, and new plugs for less than $200. For all the farting around I did trying to troubleshoot, knowing what I know now I would have just dropped $200 and replaced it all from the outset.
My 4BGE has 3 other major components that can fail:
1) Voltage Regulator. Again, if you don't exercise your genny monthly the copper slip rings inside the generator can tarnish, which increases the resistance between the brushes and the slip rings they ride on. This can damage the VR. It's about a $200 item for an aftermarket replacement from Flight Systems. Easy to replace from the front of the genny.
2) Control Board. Super easy to replace from the front of the genny on my 4BGE. Some screws, unplug some sockets. About a $150 part from Flight Systems.
3) Starter Solenoid. Easy to get at from the front of the genny on my 4BGE.
4) Fuel Pump. Hard to get at on my unit - had to drill a hole in the genny mounting pan to get access to one of the bolts that holds the pump to the side of the genny.
So on my Onan 4BGE, for about $600 I can
replace every single auxiliary component on the genny.. That's pretty much everything except the motor and the genhead.
By the way, Flight Systems will test the VR and CM for you for $20 each, and if you then buy a new board from them they will apply the test fee to the price of a new component.
One last Achilles heal for the 4BGE (and maybe other Onans) is when they moved from points ignition to a Hall Effect ICM they put the pick-up magnets on a little plastic propeller inside the generator on the shaft, in between the motor and the gen head assemblies. If critters get inside your gen head and build a nest, and you go to fire your genny up, the little plastic propeller can hit this debris and it will shear off its arms. This is a massive problem as now you have to split the generator in half by removing the gen head from the motor so you can install a new magnet rotor. On my 4BGE you can remove the ICM and look down into the genset and manually crank it over and watch the two magnet arms go round and round to see if they are there or not.
The point here is, if you can do some wrench turning, you absolutely can work on a genny yourself. There aren't that many auxiliary components that make it run, and if you buy aftermarket they are cheap, and most of them are easy to replace. The trick is to identify the Onan part number and then you can Google for aftermarket replacements. Just beware because sometimes people
claim a match for a part number when it isn't. So double-check before you buy.
Again I highly recommend the people over on the SmokeStak Onan forum for help. These guys restore old generators like some people restore old cars. This is their hobby. most of them are into bigger models than you find in RVs but they still know all about them.
The genny is not that mysterious once you look at it and understand the different components involved.
Steve
1990 Winnebago Warrior. "She may not look like much but she's got it where it counts!"