block machineing question
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From: Sitting in his Nowhere land Hanover Pa
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block machineing question
while at Carlisle yesterday I spotted a 65 396 block that had a 3-4 inch hole missing in cylinder number 6. now could that block be really saved with a sleeve? the seller was asking a good bit for it. It did have a correct Corvette assebly stamp and good looking vin stamp.
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Not for regular use, which is all my cars will see, so by my standards it is a boat anchor.
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Was the hole only through the cylinder or did it also penetrate the outside of the block? Sleeving is not the worst thing and if well done can be a very satisfactory result.
If the crack did not take out any critical surfaces such as bearing surfaces, or strength members like reinforcement webbing, and one had a very skilled and qualified cast iron welder for any outer block damage repairs (very tricky to repair), it is possible to repair; however, it would take a very valuable engine that matched a valuable car to make it worth the costs and effort, IMO.
If the crack did not take out any critical surfaces such as bearing surfaces, or strength members like reinforcement webbing, and one had a very skilled and qualified cast iron welder for any outer block damage repairs (very tricky to repair), it is possible to repair; however, it would take a very valuable engine that matched a valuable car to make it worth the costs and effort, IMO.
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From: Del Boca Vista FL
A sleeve, properly installed, is the equivalent or better than a standard casting. You know the wall thickness and you know you are centered in the bore when the sleeve is finish bored and honed.
When I was in the automotive machine shop business in the 60’s through the early 80’s our shop installed a lot of sleeves. Even as far as field installation in the chassis on farm equipment that was broken down and had no way to get it into the shop or barn. Using a portable boring bar running off a generator.
If the block you saw is truly valuable and can be saved with a sleeve there’s no reason not to do it.
When I was in the automotive machine shop business in the 60’s through the early 80’s our shop installed a lot of sleeves. Even as far as field installation in the chassis on farm equipment that was broken down and had no way to get it into the shop or barn. Using a portable boring bar running off a generator.
If the block you saw is truly valuable and can be saved with a sleeve there’s no reason not to do it.
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Team Owner
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From: Sitting in his Nowhere land Hanover Pa
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I get the sleeping process but there was a gapping hole. Does that need to be filled first?
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From: Olive branch Ms
It’s not a standard practice. Usually a sleeve is only used for a cracked cylinder. Can it be done, many many aluminum blocks have wet sleeves. They’re like sleeves for a Diesel engine but in both of those cases the sleeve is designed for that circumstance. I had a 454 block with the same issue. I can sleeve it myself, I threw it away. You have to consider how much a block moves around the when the head bolts are torqued, if the damage is too close to bolt holes the distortion would cause a leak path. If you don’t have enough area at the bottom you could have a leak there. A big black head gasket is not round if all of the sleeve isn’t out side of the fire ring compression can get to the water jacket.
