Hi all. OK...here is the update.
Got the stator back from Eurton right after the new year. The employee who does these re-winds was out with COVID 10-days before Christmas, so it was just a bit late. Any other time and it would have been a 2-week-turn. No worries there; wasn't working on it over the holidays, anyway. BTW...Eurton was SUPER easy with which to deal and I highly recommend them. My cost was $850 for the rewind plus shipping, which is just shy of $50 to NW-Florida.
As the title says, you really do not need any special tools for this job. All of the bolts that hold the top & sides on are 10mm, and you can get to all of them with a socket (or power drill/driver) except some on the bottom; those may require a 10mm wrench if behind the fuel line. Note the bottom ones only need be loosened as the sides slide 'up' out of slots.
In short, the process is:
1) Disconnect the battery and power leads (note, your transfer switch should de-energize the dual 110V leads...but I unplugged just to be sure)
2) Remove the top
3) Remove the 'front' which is the long panel on the same side as the coolant/oil caps and NOT the black/shorter end, which is actually the left side per the manual.
4) Remove the back (which is the other long side); you can leave the right side in place. That is the one with the fuel connectors and battery leads
5) Drain the coolant and remove the radiator
(LABEL ALL THE WIRES and remove them or disconnect them at this point. I put labels on each of the stator wires...there are six...red/white/black x 2)
6) Remove the inverter assembly (heavy forward unit); there are six T-30 screws on the side closest to the fan that attach to the bulkhead, a grounding T-30 screw, and two T-30s on the bottom on the top side of the intake screen. You do NOT need to remove the black/white wires above the grounding harness since that harness stays with the unit.
7) Remove the T-30 or 10mm bolt that holds the bulkhead to the base plate and rotate/bend that bulkhead slightly back to clear the fan. Since these are steel bolts and that is an aluminum baseplate, don't be surprised if that bolt sheers off. Mine did as Onan appeared to not use any anti-seize on ANY of the bolts in the base plate.
8) Remove the three 10mm bolts holding the fan to the rotor and holding the bulkhead clear, remove it. (Note: these are torqued to only 7 - 9 lb-ft)
9) Remove the four bolts holding the stator and gently slide it off the rotor. Note, the magnet will resist this a bit. Don't grind it on the rotor as you slide it off or you'll be replacing that, too!
A note on the stator. There are two sets of 3-wire induction coils. If you look carefully at the matching sets that go to the inverter, you'll see those labeled 1-1, 1-2, 1-3, 2-1, 2-2 and 2-3. When you get your stator back, it comes labeled with the leads in two groups: 1, 2, 3 and E1, E2 and E3. There were just bare leads with no spade connectors attached. Eurton gave me new male spade connectors, but those were not the right size. Fortunately, I had several that fit. Suggest getting these in advance.
Installation is the reverse of the above steps. Torque values are 7-9 lb-ft for the stator and fan bolts; the rest are specified in the Onan service manual (and are essentially snug). I took this opportunity to replace the insulation on the left (black panel with the switch and C/B) before reinstalling everything. And as mentioned earlier, I had just done the 1000hr service, replacing all the hoses. If you haven't done that and are close, now is the time since you have it all apart...just buy new band clamps as the ones on there are 'crimped' and single-use.
Labeling the wires made reassembly easier and faster. Onan does pretty much make the connectors on the inverter-to-controller fairly idiot-proof with similar-colored wires using opposite male/female connectors. Don't forget the small inductor coil that is on the output wire harness--it connects to two connectors that go into the inverter. There were two unused connectors that I am glad I labeled as otherwise I would have spent hours looking for somewhere to connect them.
After assembly, it fired up flawlessly and runs as good (and quieter thanks to the insulation) as before with no codes.
BL...this is NOT a task that requires anything more than patience, a few common tools, the service manual (available from lots of places), some 10mm socket/wrench (and driver to make it faster), and a Torx-30 driver. If you have any experience doing your own routine maintenance, this is not a hard task. Take pictures...label things...and be careful moving the stator and inverter (both are heavy).
PS...in the first picture, you might notice that black air hose at the bottom. That feeds air from the intake around to the inverter for cooling. There is NO need to disconnect or remove it. BUT...if you do remove that clamp that holds it to the air box, don't forget to re-tighten that clamp BEFORE putting the fan and inverter back into the unit. There is NO way to get to it to tighten that clamp unless you remove the fan...which requires removing the inverter...ask me how I know