Many of the stock sleeves used an upper flange. When repairing a non-sleeved block, with a sleeve, I always leave a shoulder at the bottom of the cylinder bore to press the new sleeve down against, when boring the wall to accept the sleeve. I don't think the type of sealant is a critical issue and don't think it necessary at all unless the sleeve gets wet. I chill them and install quickly but many have been done with brute force.

It takes a good bit of measuring to determine the final bore diameter for a proper sleeve "fit". The sleeves are not perfectly round so the machinist has to calculate what the press-fit diameter will be when the sleeve is compressed into a "round" bore. I shoot for a .002" interference fit. I know .001" is adequate and .003" can be squeezed in to the bore. So, if my .002" calculation is within +- .001", everything fits fine. Like Speedbump, I want the top end of the sleeve to be perfectly deck level after the excess is machined off the top of the sleeve.


There are many who consider any sealer as a barrier to heat conduction from the sleeve to the block and it makes some sense. When I use a liquid, such as in a cracked to water cylinder, I use the green LocTite metal retainer. I consider a press fit of .0015" to be great because it holds well and doesn't distort the other cylinders etc. as much. The down side of that is you REALLY have to trust your boring bar when you make the final cut. I have put them in with as much as .003" press without problems. I always leave a step at the bottom, chill the sleeve and heat the block gently with a rose bud and install quickly with a steel plate/handle I made and a 4 pound hammer. Done correctly they almost fall into place but the hammer needs to be at the ready. If the cylinder is not cracked and I'm going back to std. or .030 over at the most, I use a 3/32"-wall thickness sleeve. For cracked cylinders or larger overbores, I use a 1/4"- thick sleeve. I made a sleeve cutter out of an old boring tool for my Van Norman 777 boring bar. I center the bar and cut the sleeve wall down to within .002" of the deck and finish with a fine file and sanding block when I am not going to deck the block. This can be very important with flatheads where there's not much deck to work with. This is what I do, not gospel, but hope it helps.

I leave the step the same diameter as the orig. bore I start with. Not necessary, just my preference. I also leave the step a minimum 1/4 to 3/8 inch from the bottom of the bore. I don't measure, just eyeball it and make sure on the final pass the step is cleaned up. Most sleeves are undersized about .030 to .040 to clean up back to std. The sleeves I use are steel but I have never had a problem with ring seating. They will hone differently, sometimes, but as long as the same plateau finish is used on all cylinders, The results are excellent.

--- Warren


I like cast iron sleeves. In the parts book there is a size chart which gives bore, OD, wall, and length dimensions. The few sleeves I have done in recent past were selected from the size charts. For example, a sleeve for 3 3/8" bore hot rod Flathead can be from a Corvair. L.A. Sleeve can come up with any size sleeve you need. Also, repair sleeves are still listed in the Federal-Mogul Catalog for 39-53 engines and described as 3.377 diameter with a special note that grinding will be necessary in blocks which are relieved.

If the sleeve is going to be installed, where the original wall remains for support, the shoulder at the bottom can be about any length from .250", to .500". However, if there is no wall remaining you have to be very careful because the bottom of the jacket is only .260 thick, in our flatheads, and is not perfectly perpendicular with the bore. In some cases I put small screws threaded half into the sleeve OD and butted against the bottom of the jacket where there is no, or minimal shoulder available.


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