Resleeving cylinders

[Robert C.]

If anyone out there has experience with a resleeved engine cylinders, please comment. There's a 63' 340hp car here in my area that the owner had ALL 8 cylinders sleeved. What do you think the short and long term prognosis for this engine will be?

[Chuck G.]

Re: Resleeving cylinders

I'm no expert machinist, but most that I've talked to tell me that the sleeves are better than the original block casting. Diesel's commonly use "wet" sleeves. When they wear out, they just pop in new ones...after 200K miles or so. I don't see a problem, as long as they were installed correctly. Chuck

[Bill Baird]

Re: Resleeving cylinders

A buddy of mine had one of the cylinders in his '64 coupe re-sleeved. The machine shop that performed the work said the same thing as Chuck: as long as the sleeve is installed correctly, there should be no problem with a re-sleeved cylinder.

Bill Baird

[Joe L.]

Re: Resleeving cylinders

Bob-----

I totally agree with Chuck. I really believe that the perceived "undesirability" of sleeved cylinders is ill-founded.

Bear in mind that there are two basic types of sleeves. The first, a "wet" sleeve as Chuck also mentioned, is a design in which the outer wall of the sleeve actually contacts the engine water jacket. This type of sleeve is primarily found in diesel or other heavy duty type engines, although it has been used in some automotive applications. This type of sleeve is sometimes thought to be "better" since there is no metal-to-metal interface to, theoretically, impede heat transfer between the block material and the sleeve. However, these engines are generally designed around the use of "wet" sleves for reasons other than this theoretical "asset".

The second type of sleeve is a "dry" sleeve. In this design, the sleeve is either pressed into an enlarged bore or, in some cases, is incorporated into the block at the time of its casting. The cast iron sleeves used in the new Corvette LS-1 aluminum cylinder blocks are of this type. These sleeves cannot be removed for replacement.

Save for some ill-fated 1969-era aluminum big blocks used primarily for Can-Am engines and the short-lived Chevrolet Vega engine block, virtually all aluminum engines use "dry" cast iron sleeves.

Many engines with cast iron cylinder blocks can be salvaged and repaired with the use of a sleeve or sleeves if a cylinder or cylinders are damaged or previously overbored to the limit. In addition to repairing and saving the block, the block can also be returned to "standard" bore size using sleeves. This is especially true for an engine which has suffered damage to one cylinder, but where all other cylinders are satisfactory at their original standard bore. Rather than over-boring all cylinders to correct the deficiency of one, the one cylinder can be sleeved and restored to standard bore. Also, an engine which has been previously over-bored to the limit and is now worn can be sleeved in all cylinders and restored to a "new life".

There are only two "downsides" to sleeving. First is the notion that the sleeve-to-cylinder block interference fit interface will impede engine cooling. This may occur to some minor degree, but I believe that it's vastly overrated as a real concern.The fact is that there are many engines running around with dry sleeves that don't have cooling problems. As I mentioned, virtually all aluminum block engines have them. Of course, it is true that in this case you have an aluminum block-to cast iron sleeve interface, but the impediment to cooling represented by the interference fit interface is just as real as with cast iron blocks. It just really isn't a significant problem with EITHER type of block substrate material.

The other "downside" to sleeving relates to cost. With most engines, the cost of sleeving cannot be justified versus the cost of obtaining a new block "core". Most engine cores are rather plentiful and cheap. If more than one sleeve is required the economics usually really favors replacement.

However, many blocks have inherent and intrinsic value to the owner. Rare blocks or original engines for collector cars(like Corvettes, by the way), are among those where sleeving is worth the cost, even if all 8 need to be done.

Also, as Chuck mentioned, the quality of the material used for cast iron sleeves is usually much better than the substrate block material. Most cast iron engine blocks are cast from gray iron, the least desirable type of cast iron. Replacement sleeves, on the other hand, are usually constructed of ductile or nodular iron, which is significantly superior.

[Leroy Lemmerhirt]

Re: Resleeving cylinders

I sleeved all 8 cylinders in my 409 Chevy--block had been bored too far-- no problems--runs cool. Rather expensive but saved a hard to replace correct engine.

[John F.]

Re: Resleeving cylinders

Bob,

Joe is right, it will work well but it's not cheap. I'm spending $400 right now to "black sleeve" one cylinder which lost a fight with a rod. However, the real cost adds up after that, because hey, why not balance and blueprint the engine while I'm there. Then the heads might as well be tuned up. Then why not rebuild the distributor, alternator, starter...Now I know how frame off's get started! Hopefully it goes back into the car next week because the sun is starting to shine.

Good luck. John

[Robert C.]

Re: Joe, You're Unbelievable!

Your expert advise is appreciated by ,I'm sure, everyone that reads the Board! I would love to know your background, what kind of Corvette you own (if you do),and if you are independently wealthy???( You're always here) Please give us all a chance to know you a little better. Thank you so much for your valued help and direction. Bob

[motorman]

Re: Resleeving cylinders

make sure that the block is stepped sleeved,the sleeves donot go through the bottom of the cly. look for a parting line at the very bottom of the bore where the sleeve is seated on the block orignal bore.this prevents the sleeve from sliding down the bore. :(

[Joe L.]

Re: Joe, You're Unbelievable!

Bob-----

Well, I can assure you that I'm NOT independently wealthy; I'm a "working guy" like most of the rest of you out there. However, I'm "chained to my desk" most of the time these days and take breaks to check the Board frequently. Usually, when I'm in my office, my responses are pretty quickly generated since I'm mostly operating from memory; I keep VERY few Corvette references here in the office.

As far as a little information about me for yourself and those who might be interested, I'm a microbiologist by profession and and an administrator of a governmental water quality environmental regulatory program by trade. I've worked in this capacity for virtually all of my post-college working career which is now just 5 months short of 30 years. I've never really had any formal automotive training or even high school auto-shop inasmuch as I was in a "college prep" curriculum while in high school. When I was in high school, I worked part time for two years between 1963 to 1965 at a Chevron Service Station that belonged to a friend of my father's. But, outside of that experience, I've never worked in the automotive industry in any capacity, at all. However, automobiles, and particularly Corvettes, have been a hobby for me since I was in junior high school. I've studied the subject pretty intensively. In the mid 60s I factory-ordered and purchased two Chevelle SS396 cars; a yellow 1966 with 396/360 hp and M-21 and a black 1968 with 396/375hp and M-22. I sold the latter car when I bought my first Corvette.

Regarding what Corvettes I own, I have two, both of which I factory-ordered and purchased new. One is a 1969 convertible, riverside gold, with a 350/300 and M-20(soon to be a "ZL-1" with M-22 on an "interim" basis). My other Corvette is a 1992 yellow coupe with LT-1 engine and 6-speed ZF trans. The 69 was my daily driver from September 30, 1969(the day I took delivery) until April, 1977. The 1992 was my daily driver from November 24, 1991 until December, 1993. Both are now used for "pleasure" use only.

With the exception of some warranty work performed on both cars VERY early in their lives(at less than 5,000 miles in the case of both cars), I am the only one that has EVER worked on either car.The 69 currently has EXACTLY 200,000 miles on the car and the 92 has about 36,000.

I have never owned any other Corvettes and I've never sold a Corvette or bought a used Corvette. I've been collecting NOS parts for the 69 for well over 25 years and currently have over 5,000 in my collection(none of which are for sale)and I've also collected a few hundred for the 92.

Joe Lucia NCRS #12484

[Robert C.]

Re: Joe, You're Unbelievable!

Thanks Joe for the review. Please keep up the great work. I hope you come to some of the NCRS judging events. You would make an excellent judge! I hope to meet you in person one of these days. Good luck with your '69! Thanks again, Bob #23234.