Sounds like you need to find a new machinist.... a competent one this
time.... and a new block while you are at it. A competent automotive
machinist should have been able to sleeve your MGA or MGB engine without
destroying it in the process. There is nothing wrong with sleeving if it is
done correctly.
David Littlefield wrote:
> On Fri, 24 Aug 2001 14:46:44 -0400 "James H. Nazarian, Ph.D."
> <microdoc@apk.net> writes:
> > IMHO, if the engine needs to be rebored because one or more cylinders
> > are worn out of round, deeply scored, or otherwise damaged, yet the
> > pistons and their grooves are in good shape, I would be more
> > inclined to have the cylinder, or cylinders "sleeved". An automotive
> > machine shop can install a sleeve for little more than the cost of a
> > cylinder re-bore, while saving you from buying a new set of pistons,
> > etc. Furthermore, the sleeve that Moss sold to me several years ago
> > was a Mazda OEM part. I assume that there
> > were some metallurgical improvements imparted to my 1974 British
> > engine by the use of a 1994 Japanese sleeve; only time will tell.
> > The cost savings, however, were substantial and immediate.
>
> I'm not sure I would sleeve a block just to save the cost of new pistons.
> Sleeving requires overboring the cylinders then having a sleeve put in
> place through an "interference fit." The sleeve is also kept from moving
> around by the head on top and a "step" on the bottom of the cylinder. If
> something goes wrong in the sleeving process the bottom step can be
> broken. You then risk the sleeve moving down into the block and leaving
> a gap at the top and eventually fouling something. The sleeve can then
> be welded in place, but you are welding it to cast iron, which is a dicey
> thing.
>
> How do I know all this? Because my MGA 1622 block is sitting in a box
> with a broken step and a welded sleeve and it needs a new set of sleeves.
> My machinist said he "couldn't be responsible" for the result and felt
> that it would not be a very durable engine.
>
> Of course, if the cylinders are too badly worn or scored, you'll have no
> choice but to sleeve the block. I just wouldn't take the risk to avoid
> the cost of new pistons. My machinist quoted me about $100 per bore to
> sleeve a block, but I don't recall how much to bore each cylinder. 1275
> pistons are not all that expensive at less than $200 from Moss (with
> dealer discounts). And then you would have new pistons with new wrist
> pins, etc.
>
> Just MHO.
>
> David Littlefield
> '62 MGA MkII
> '51 MGTD
> '74 MG Midget vintage racer
> '88 Jaguar XJ-S
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--
Jim
microdoc@apk.net
1999 BMW R1100RT Very Black... of course
BMW RA #25289 MOA #89329
1972 Suzuki TS185 Dual Sport, Very sort of orange. For Sale
2000 Audi A4 Quattro Avant Very Silver
1960 MGA 1600 Very Red
1974 MGB-GT Damask Red (Very Burgundy)
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