as to the separating of cylinders . . . one of the most common issues in the past is that sleeves were fit with too high an interference value on cylinders that were already thin and may/may not have had their bore centerline square with the base flange after several rebores. This is especially true on iron/iron motors which tend to behave a bit differently when bolted down and fully warm than alloy/iron or alloy/alloy combinations. Many "vintage" motors also do not have through studs and substantial force is present at the cylinder base/case/spigot interface. Failure to double check the spigot to case clearance can cause issues blamed on the sleeving process as can torque induced distortion of the entire barrel.
When done with care and attention to detail, there is no reason a sleeve cannot outlive a non-sleeved cylinder.
The boreman didn't even sharpen the tool for cutting the casting, leaving such chatter and toolmark that it insulated the Chief sleeve shown in the attachment.
A thou and a half is all that's necessary to hold the sleeve, and transfer heat, but it sure helps to hone the casting to a fine finish.
This one required an expensive over-size LA replacement.
When the final bore was finished for the piston, it still distorted dramatically more than a stock cylinder when torque-plated.
....Cotten
Last edited by T. Cotten; 06-20-2019 at 04:22 PM.
AMCA #776
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The only bad outcome in which I know a LASCO product was employed was several U/UL (11 fin, 120-38/381) cylinders, originally 3-5/16" bore, which had VL/UH/ULH sleeves (3-27/64" ID, 3-9/16" OD) installed. AFAIK not LASCO's fault, some shop didn't see a UL sleeve (their EL sleeve is the right OD but too short) and bought the wrong one.
The cylinders cracked across at the guide ledge, being the large change in cross-section plus the valve spring levering upward from the pinion side.
They claimed to be able to put as much as .05" per wall, and then hone it with special diamond tools. In that process no additional cylinder material is lost. I have not used them myself, but they do hundreds of cylinders a month and seem to understand exactly what they are doing.
The LA Sleeves in my '48 Chief have been working great for over 20 years now. I am so pleased that I had that company sleeve my '56 KHK this year.
The original Nikasil cylinders are doing fine in my 1984 Moto Guzzi V65Sp; so, that approach is also excellent -- if you have enough good metal left in your cylinders.
Just had LA Sleeves do a set of their sleeves installed in some oversize OEM knuck cylinders. My buddy had a set done 20+/- years ago and they were fine. Based upon that, we opted to do use them again. So far, so good.
They do seem VERY knowledgeable.
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