4.2 litre rebuid prob

returned to the shop from the machine shop, they were told there was a small "scour" on one cylinder wall.

option he said was to buy oversized

it. Does this make sense, and is it right? I am concerned about

familiar with this?

That used to be standard practice on the very old days . Some high performance motor made of magnesium use to have sleeves . Peugeot 203 also, had them . It was the head gasket that kept them in place but the block was designed to accept them.

It's OK to sleeve any engine.

As long as it's done by a reputable machine shop.

I'm pretty sure many engines have sleeves from the factory. Aluminum block engines use iron sleeves or steel sleeves (can't recall which one) since aluminum is so soft. As long as it is done properly, it is fine. It must be a snug fit so it transfers heat to the old cylinder wall well, but I'm sure that a machine shop can handle it.

Bill

I now have the motor installed. The cylinder wall "scour" is all o.k., very slight, and will not hurt the rings. Problem now is there is a "miss" in the engine. All rebuilt - timing chain, valves, guides, camshafts, rings, seals, gaskets, heads, etc. My mechanic thinks there might be a problem on one set of valves, he is installing a new set today. On that cylinder, there is no measured compression due to a probable valve "shim" problem, but all is perfect on the leak down test so the bottom of the motor is alright for sure. Where do we go from here? Any suggestions? Regards, Tony Pike. "Tony Pike" wrote in message news:WmeEj.115279$w57.3347@edtnps90... I am getting my 4.2 L motor professionally totally rebuilt. When the block returned to the shop from the machine shop, they were told there was a small "scour" on one cylinder wall. My mechanic thinks it should still be o.k., he had a visual, but another option he said was to buy oversized pistons (too pricey). He recommended to hone the wall and press a sleeve into it. Does this make sense, and is it right? I am concerned about metallurgical probs here, although the sleeve is made by Mercedes. Anyone familiar with this? Thanks, Tony...

A valve is probably not closing, but why??

I believe they use shims, and they were installed improperly? They did a "leak down" test, I never heard of this before. On all cylinders, they remove the spark plugs and perform a pressure test, all check out fine. BUT, the compression test failed completely on one cylinder - showing that the valves were not operating correctly. When I find out what happened, I will repost to share the knowledge. They rebuilt a Dodge Intrepid for $2,000.00 and no problem. My motor is now in the neibourhood of $7,300.00 , and I hope all will be good. My mechanic told me a new factory motor is $17,000.00 AND a typical rebuilt motor would be $10,000.00 . He claims he has lost on this deal already... Regards, Tony Pike. "-->> T.G. Lambach

Don't believe those prices... just check with Metric Motors or Noel Mercedes in FL for the current price.

I did check online and it seems most places want $8,000.00 to rebuild the