Well, I got a little more time to work on the Onan. I didn't try to start because the po said it wouldn't run so I figured I would dig into it.
I pulled the flywheel and found that the keyway was sheared off. The P series have an electronic ignition and the keyway fits into the pickup ring on the crank to keep the timing correct. Problem #1 found. Here is what it should look like.
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To remove the crank you need to remove the gear on it and that requires a special tool that I don't have.
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The Onan rebuild on MTF had a homemade tool so I searched my junk and found something that should work. It was a split taper bushing that are used on sheaves. The center hole is a little big but it worked. I cut the back part of it off and drilled two holes for the (2) 10-32 allen head screws that are screwed into the gear to pull it. I tried my gear puller but I couldn't get a good straight pull on it so I used this puller. It was on there tight but it worked.
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Here is why I'm changing the crank. The po cut it off and also the foot on the oil pan. This plate comes off so the crank can come out. Here is what the main crank bearings look like in an Onan.
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