So the generator saga continues. All worked well for several hours then back to intermittent operation as described above then nothing and the overheating began. The 4A field breaker popped again and once it cooled down and I was able to reset it, nothing... a little over 18V across the output/breaker legs. Next morning troubleshooting showed 13.2-13.3 ohms on the exciter stator, supposed to be 23-28 according to manual. Pulled off the end cap - which does NOT support the end bearing of the generator end - so you can pull and blow out and clean out that end cap screen (mine had a few big leaves in it). Found the exciter stator has one of the 2 wires that go between the 6 coils popped off. I'm guessing its a double wound stator as I get 13.2 ohms, half of the 23-28 ohms. Tech support said it's not enough resistance to trigger the voltage regulator soooo... generator no work-y. It makes since looking back at all the problems (different) I was having to this point of complete failure. The insulation was holding the broken wire together then it eventually let go. I bet my old voltage regulator is not bad... At least I have the correct one in there now and 2 spares... LOL.
New exciter stator purchased from Power Tech this morning $1215.95 + ridiculous amount for overnight shipping. Parts lady said wow that's an old generator, 1996... It only has 2700 hours on it, engine runs great. Part of buying/owning anything old. The insulation on the wires reminded me of the Vietnam era A4's and F4's i worked on in the military in the early 90's - wire insulation, especially the old varnish/shellac insulation, is cracked and flaky. Well it's just another part. While this initially seems a bit intimidating, it's actually quite easy to get at and swap: Pull the squirl cage, pull the end cap/plate, then the 3 bolts holding the stator. I did have to remove the 4 nuts holding the control box to the generator so I could cut the zip-tie between the control box and generator that has feed/power wires from the main stator to the main breaker and the exciter stator wires (zip-tied in a bundle). I have the "M" style generator, which I'm assuming stands for Marathon which sems to be the manufacturer of the generator end. It's looking like Power Tech is like Lotus cars, they build a chassis then piece together parts from everyone else - in this case, engine from Kubota, generator from marathon, etc..
We'll know tomorrow when the exciter stator arrives - hopefully it's be good for another 27 years.
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