A little longer than expected waiting on the stator rewind. Stator was actually ready Monday but he was waiting on a super hard insulating varnish that came in today (Wednesday) so I picked up the stator at almost 6pm. He explained that he used American wire with #6 insulation vs the cheaper Chinese which only has #2 insulation - I haven't researched what that means yet but I will. Likewise the varnish he used is a super high temp and very hard - perfect to be stuck in a hot generator compartment. He also explained that it was wound in 2 windings so you could have half of the stator fail like the old one did, reason I was getting 13ohms on the old/failed stator. Re-wound stator Ohmed out at 20.2, a little lower than the factory 23-28 but more than the 15 required to trigger the voltage regulator. Install was quick except for a trip to the parts store for 2 ring terminals to connect the stator to the terminal strip with the voltage regulator - it's always the little things. Then I fired it up and had just under 6 VAC, never jumped up to the 240vac (measuring across L1 & L2) which after investigation (RTFM for the VR) and the VR will not fire unless it sees 6VAC or more. Remember i was seeing just over 18vac on working old stator. So I flashed the excitor stator as there probably was little to no residual magnetism in it being basically new. That is a super simple process that is a bit scary to do for 1st timers, me. I've never had to do this before so I did a lot of reading and then took a leap of faith and did it. Basically you take the 2 wires off the exciter stator (the ones that go the F+ and F- on the VR) and touch them to 12vdc for 3 seconds, reconnect and check for AC voltage. You first ohm the leads and make sure you're good there (20.2 ohms in my case). The I ohmed from each lead to ground to make darn sure I was not grounded out (from install or otherwise). For ease sake I simply unplugged the F+ & F- leads from the VR, took 2 pieces of wire about 2" long each, stripped both ends and stuffed one end in the female spade connector and touched the F- lead to ground and the F+ lead to the 12vdc on the starter solenoid in the control box. It makes a small spark when you remove the lead (for me I removed the +12vdc lead) which makes since as the magnetic field collapsed and well, inductive kickback, just like an ignition coli & spark plug. This time I got just under 10vac when I connected the exciter stator to the VR, over 6VAC to trigger the VR but still no 240vac. So I flashed the field a 2nd time and got just over 18vac (as per the manual for the VR, rinse and repeat on field flashing) - I was happy with that, but still no 240VAC.... So I try the old VR that was in the gen when I bought the RV, no luck. Then I pulled out that one brand new spare AVC63-4 and voila - 198vac (FYI Auto Voltage Controller 63VDC-4A) - Now to buy another $229 spare, apparently they are now bad from the failing stator..... Pulled out the screw driver and turned the voltage pot to 238VAC, turned the stability pot to full clockwise as per the VR manual and centered the under freq pot. Ran it for an hour, turned on every load in the bus and boy do I need to load balance the legs. One leg is hitting 55A and the other barely 15A. If I move just the water heater and insta-hot over that will put it at 25A and 35A which is much better. I didn't get to the bearing with all the other projects on the bus, however it seems pretty straight forward and easy enough to swap.
Summary - $800 and 10 days for a stator rewind at a local shop. AVC63-4 Voltage regulators 3 @ $230/ea - original one was wrong one (Bassler SE350) according to Power Tech but it worked - I bought 2 new ones, failing old stator fried the original and 1 of the new ones. Changing water pump and almost all radiator hoses, new radiator caps, 3 sets of filters (2 spare sets), spare belt, installed manual on/off switch, replaced 40A start circuit CB, changed/upgraded all 3 cooling fan wiring, new antifreeze and synthetic oil roughly $900. Grand total roughly $2200 my labor is of course free but generator should be good for a long while now with plenty of spares with filters for at least 750hrs of run time. Way less than the $6k the generator service wanted to charge and that didn't include VR's, spares or a stator rewind. I encourage anyone to tackle this yourselves, once you're done that generator will no longer me a magical power maker and you'll be very equipped to handle anything it throws at you in the future.
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