I've put my SS180 motor together with new bearings and new seals. The old crank shaft that was in it was toast. The threads and bearing seats were thrashed. So, I found an original one that looks to be in great shape.
There is problem. When the flywheel and flywheel hub are tightened down on the crankshaft, it will turn freely about half way through the revolution and then the fly wheel rubs badly on the top edge of the aluminum motor case. To me, it appears the crank is not straight. There are no binding issues with the cylinder head and piston.
The SS180 flywheel is two parts, a flywheel and a steel hub bolted in the center of the flywheel. If I remove the flywheel from the steel hub leaving the steel hub in place and rotate it with a ratchet, I can see that the hub oscillates irregularly instead of spinning straight. I have another flywheel and tried it and it's the same problem
Is this an indication that this crankshaft is bent and a serious issue?
My GS160 flywheel is not like this at all. It spins straight, nice and smooth.
The last thing I want to do is get it all done, start it and watch it all get chewed to oblivion before my eyes.
If anyone has any thoughts, I'd appreciate it.