wen i was putting the pistons back in my engine on my 76 olympique, one of the cylenders cracked at the bottom of the bore. Can i still run my engine with a crack in it? also, the rings don't fit their about .002 " off. should i bore it at a shop or hone it out myself?

I wouldn't use a cracked cylinder, if the piece breaks off it would more than likely take out the crank and crank-case, so it's just not worth the gamble. You should be able to pick up a used cylinder pretty reasonable.

BTW what do you mean the rings don't fit? Ring end gap should be .010 to .063"

without the rings the piston slides all the way through. with, the rings cracked the cylender. where could i find a cylender, and could i just have mine sleeved?

Depending on engine size, piston to cylinder clearance should be from .002 to .007". Measure the clearance with feeler gauges. What size engine do you have?
Did you buy oversize pistons/rings? Try a snowmobile wrecker, they should have cylinders pretty cheap for that old model.

its a 343. the bore is like 59.5mm and the piston is 59.5mm. its the smallest they had. the crack is a hairline crack below where the piston travels. its really tight to the point i can't pull it open.

You'll have to fix it with a cardboard box. Put everything in a cardboard box and drop it off at the nearest automotive machine shop.

OK, for the 343 the piston clearance should be .0031 to .0079 inch, put the piston into the cylinder and slide a feeler gauge up the side and see what you have. Measure at right angle from the piston pin.

Take the rings one at a time and put them into the cylinder bore, push them down nice and square with the piston and place in a spot with no port openings, slide a feeler gauge into the gap..........it should be between .010 and .063 inch. If it's less, carefully file the ring ends until you get .010 inch clearance.

When installing the piston make sure you have the ring gap where the pin is in the groove. Use lots of oil when installing and make sure you have the arrow on the piston pointing to the exhaust port, IF you have all these clearances as per spec. it should be good as new.

i bought a engine on ebay. its the same engine so i'm just gonna pull the cylinder off that. thst should work right?

Originally posted by spyderrocs@Jul 30 2004, 07:13 PM
i bought a engine on ebay. its the same engine so i'm just gonna pull the cylinder off that. thst should work right?


If it's the same engine, it should work.