Tuesday, April 7, 2009

ZA50 Part 3


As I reassembled the motor, I found that I hadn't clearanced the case enough, and my piston hit the edges of the bottom, as you can see in the top left corner of the piston here. I know, a piston is round and can't have a corner, but use your imagination. So apart it comes again, a little more dremel and it's back together. Then I gaped the rings properly to .014, and then also found the piston wouldn't fall through the cylinder with the rings removed. So after dropping it from each side and switched around I found it was hanging up at the cylinder skirt, and not clearning the exhaust port. So after some honing I was able to get the piston to drop almost all the way out, which was good enough for me, since it really only needs to smoothly clear the exhaust port, which it does. Kind of curious about the quality of the kit, but it looks solid, even though it needed quite a few touch ups. The ports were razor sharp, so I took a riffing file in there and smoothed 'em out. That slop in the bushing I was talking about has been remedied, Michael Mike Naz spent a few hours on the lathe turning me out a beautiful example. A little bit of finish work once it was pressed onto the crank and the bellhousing spins like a mad man, only it doesn't slop around anymore. It took a little bit of encouragement to make sure the oil holes lined up. I finished my re-assembly, oiled it up and I'm going to toss it on the Magnum right now. Hooray!

2 comments:

naz said...

Yup, I made that, sure doesn't look very exciting in the photo....

-naz

Philip Patrie said...

I should have taken a high-speed action photo of it, where the back ground is all blurry.