Ok, compression on both cylinders was 85 and 80. Not good enough.



Put a little oil in the cylinders and compression shot up to 110 on both. So rings are gone. Weird thing is, I pulled the jugs off and it looks like it's had a recent top end job done.

Sure enough, the compression rings were on upside down and in the wrong order.

Pistons are brand new (020) and everything looks clean, there are still fresh hatch markings on the cylinder walls, but I'm going to order new rings and deglaze the cylinders. I have a friend who does a lot of work on old shovels, pans, and knucks and he's not really seen this stamp on a piston?

I'm sure someone here would know.

"1200 (SC)"

 

i believe its a china cheap copy from life line the bottom of the barrel

mid usa are imports as well and i have installed hundreds of sets just buy the hastings moly ring package

V twin pistons are imports as well and have used hundreds of those as well with the hastings ring pack But the rings that come with those rings only as a set is cast not moly

KB pistons are junk like the one you have - some people have had luck with KB pistons but i have not for what its worth - the cast pistons we install i set at .003 the KB stuff is .0008 to .0012 no good with the gas we have today

 

Thanks for the info, that was a huge help!

 

I ordered and received a set of Hastings rings I was hoping someone could clear up a questions about the compression rings.

The second ring has the usual dot marked on the top of the ring so I know what side is up. The 1st compression ring doesn't seem to have any markers at all. I would assume that this one can go in either way? Hoping someone has used these rings before and can let me know.

Also, I've seen a lot of different thoughts of staggering the ring gaps and I was hoping some folks would offer up what they think is the best way?

 

top ring is non directional

what i do not whats in the harley book in a 1000 engines

draw a clock circle with the numbers standing on the right side of the bike -

top ring is at 8 oclock

second ring with dot up at 2 oclock

center oil ring expander at 8 oclock

top oil rail ring at 11 oclock

bottom oil ring at 5 oclock

this is how i have been doing it in my shop since the 60s

 

Johnjzjz...I think for my next reading project I'm gonna wade through all your posts.

 

If you've been doing it that was for that long, then that's exactly how I'm doing it. Thanks so much.

 

unless it's marked it doesn't matter about up or down

I'm a 180 guy placing the gap inline with each side of the wrist pin. Instead of the triangle way