Snowmobile Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
I think I know the answer to this.... but should I rebuild the whole engine or do I have to just re-do the top end? While I have it apart is it best to change all the seals and bearings in the lower end?

Thanks in advance......
 

Attachments

·
Registered
Joined
·
5 Posts
Discussion Starter #3
Wow... thanks for the speedy reply....

one more thing, the pistons have 020 stamped on the top, is that the standard size or has this engine been done once before?

Cheers
 

·
Super Moderator
Joined
·
16,804 Posts
Not sure on the markings, you should mic the cylinders before putting a new piston in to ensure the cylinders are spec either way. And as RJ said, figure out what caused the lean condition and fix that or you will be doing the pistons all over again. Usually, on the PTO side, it's the crankcase seal, but it could be jetting or carburator related as well.
 

·
Certified Mechanic
Joined
·
56 Posts
If the piston shattered I would suggest rebuilding the entire engine. If there was a hole burned through, you can probably get away with just replacing the one piston/ring. Check the sleeve for any gouges or wearing; usually around the intake and exhaust ports. If slightly worn, you can hone out the cylinder or have a repair shop do it for pretty cheap. You can then replace the "burned" piston with the new one; make sure it is facing the right way; usually an arrow indicating the front. Also make sure the ring is facing the right way wtih the tapered edge on the top; the tapered edge is what helps hold oil and distributes along the cylinder wall. Once everything is back in place and tightened down, run a little extra oil through the first tank; add about two or three caps full of whatever 2-cycle oil into your fuel to help lubricate the new piston.
 
1 - 7 of 7 Posts
Top