In <MAILQUEUE-101.950329101818.992@acad1.unbsj.ca>, SEAN M. DRISCOLL wrote:
> I recently purchased my first MG and I was wondering what is
>considered to be high miles on a B engine. I would like you to assume
>that the car has been driven relatively easy, and regular tune ups
>and oil changes were accomplished. I would appreciate any and all
>answers to the question. The only answer I have aquired thus far is
>from an uncle who claims that no more than 30 to 35 000 miles cen be
>reached before doing a complete rebuild.
This is a good question that has not surfaced recently. At some
slight risk of flame attraction, engine blocks on British cars seem to
be made out of fine cheese. It has been my experience that with
average use MG blocks can go something like 60-80,000 miles before
needing serious attention, but that is really lousy when compared to
the robustness of engines from our friends in the Far East, which can
often go 150,000 miles or more before getting too loose. The most
common problem is cylinder wall wear (and the accompanying loss of
ring seal). When the bores get to be more than 0.005" oval, or the
bottom is 0.010" bigger than the top, the pistons start swapping
holes, or at least applauding madly. It is rare that I have seen an
MG block that has not been overbored at least 0.020", except in a
junkyard. At least on B's, aside from cracks in the air injection
heads, the heads seem to go on rather longer, and bearings are rarely
a significant problem, although replacement of bearings when one does
a bore is axiomatic.
There are a number of ways of telling whether your block needs
attention without taking it apart, but that has been pretty
thoroughly thrashed on the net so if you need more info contact me
via e-mail.
A. B. Bonds
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