Quote:
Originally Posted by Schurkey
Ideally, the sleeve sits on a "shelf" of original block material near the bottom of the bore. The shelf prevents the sleeve from migrating down the cylinder wall under compression from the head and the fire-ring of the head gasket.
No shelf...I'd be VERY suspicious of that block. Sounds like it was sleeved by someone who didn't know what they were doing.
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This very thing happened to a friend of mine that built a 350 chevy for another stock car racer friend, he did it for free too. The sleeve had no ledge left on the block to hold it in place, and during the first night the engine was in the car the sleeve started it's decent into the block, all the while breaking apart as the crank counterweights hammered the sleeve, and block to pieces, totally destroying the engine during the feature race. The owner/driver wouldn't back off of it even though it was smoking and slowing down, maybe some of the parts could have been saved if he had. When it finally scattered there wasn't a thing but the cylinder heads, and the intake manifold that were salvageable.
The guy that bored the block was unfamiliar with installing a sleeve and bored it the same way he would have bored it oversize for a larger piston, all the way through to the crankcase. A lot of hot tempers over that fiasco. Although it wasn't the fault of my friend, the machine shop took no blame for the mistake. I have no idea if the two former friends ever got past the engine blowing up. Last I knew they weren't speaking, and this was probably 25-30 years ago.
Be aware of what can happen if the sleeve doesn't have a ledge to rest on at the bottom of the cylinder.
On engines designed with replaceable sleeves, (usually diesels) there is usually a flange of the top that sits into a recess on the top of the block, sandwiches between the block and the cylinder head that locates it. Most automotive engines don't have room for a flanged sleeve and must have the step at the bottom to locate the sleeve. Without that step, the sleeve is free to move downward causing the mayhem I already outlined.
Sleeving all the cylinders in a block is risky as it severely compromises the strength of two adjacent cylinders. This very topic was discussed within the last year, and one of the members that was an machinist, said the would never do more than 50% 0f the cylinders in any block, and no two cylinders adjacent to each other, FWIW.