I am trying to assemble the bottom end of a polaris 350 engine. The problem is the crank spins freely and then when you put it in the cases it is really hard to turn it. And then when you put the case on over the water pump it barely even moves. All the bearings are completely soaked in oil, and the seals are greased. I assembled it 2 times and got the same results. I tightened all the bolts to spec and in the correct order according to my manual. I just can't seem to figure this out so if anyone has any info on this I would appreciate it.

 

sound like you didnt measure the end play in the crank bearings or added or subtracted wrong if you did. the bearings and crank assembly is wider than the crankcase is and they are binding. there should have been shims behind the bearings on one side. remeasure and remove as needed. the end play should be around .008 - .012.

 

Okay what exactly are these shims? I bought this bike in peices and I don't think they gave them to me. I do see the problem now. The Crank is rubbing against the bearing on the water pump side.