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Some time ago Mike Wodkowski was having generator trouble in Brooklin and I sent him a good generator from here to exchange for the nearly new Bosch rebuilt which had failed on him. I've been sitting on his failed generator, waiting for time to work it over. I finally found the time, and here's what I found. There was solder from the armature that had melted and had been flung out against the inside of the generator housing. At first this led me to assume that for some reason this generator had been asked to put out too much current. This would not have been possible if the voltage regulator and the wiring were operation properly, but Mike's VR was new and he had checked the wiring and it seemed fine. I tried to run the generator as a motor, which is a good test of whether it is working or not. It failed--did not run at all from any position. The thru bolts on this generator were tighter than any I've ever dealt with before. I had to borrow an impact driver to get them loose. I've never had any trouble before, but this was not really a problem. Once inside, I could see that the commutator was burned in a particular pattern that looked kind of like a skid mark that ended abruptly at one point on the commutator. I suspected that there was a problem with the armature, but couldn't really find anything wrong. It appeated that the burned part of the commutator had overheated from arcing and that this was where the solder had come from. This past week I finally got around to making a jig to turn the commutator in a lathe. One of my co-workers suggested that the burn mark MIGHT be caused by the commutator being turned off center. In fact, that's what I found. I was able to check the roundness by carefully starting my cut in an area where the brushes hadn't touched the segments, so that I was working on the surface as it was when last turned. An initial cut there didn't even come close to cleaning up the surface. After turning the commutator round again, I tried running it as a motor and it ran just fine, so I think everything else is okay now, and Mike's only problem was a poorly rebuilt generator. It appears that the solder that was flung out was not enough to hurt anything, but I can replace it if necessary. Mike has a good replacement now, so I think that he will be in good shape for a long time. I still need to find a way to undercut the mica easily, and then I can put his old generator back in service. -- ******************************* Jim Adney, jadney@vwtype3.org Madison, Wisconsin, USA ******************************* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org