I pulled the starter motor off the machine, and when I started to loosen the 2 screws that hold the case together, oil started to seep out. Then a lot of oil !!
The starter was full of oil. Inside was a black sticky mess of carbon dust from the brushes mixed with oil. I cleaned both end caps and all insides with kerosene, and blew it out with air. Put it back together, bench tested it, installed it, and it works perfectly.
The starter is sealed and not vented. There is an oil seal behind the drive gear that works in the wet side cover with the flywheel. So how did the starter get full of oil?? I talked to 2 Polaris dealers, both never heard of this. I talked to a starter rebuilder near where I live, and he says this is the 3rd one he has seen soaked in oil. My only thoughts are either a bad seal on the starter shaft (but how did that much oil get in there?) or, the side case somehow got pressurized (bad vent) although I didn’t find a problem.
Anybody seen this, or have any thoughts? I don’t want it to happen again.