Stuart,
I bought the crank from a supplier recommended by the machine shop. The
supplier has over 30yrs experience in these things and is a reknowned
vintage race car builder. I simply drove the crank from his place straight
to the machinist. I certainly am too much of a trusting soul I guess, and
should have measured the crank myself at the shop prior to purchase, so I do
take _some_ of the blame - but - I find it hard to question someone with so
much experience who states to me - 'I'm positive, it's a Mk1 crank - no
worries mate!' (after asking the question 3 times with the same answer. the
guy had 6 MG racecars being worked on in there so who am I to question his
knowledge..!!). I exempt the machine shop from this now, as thanks to the
list I now understand they don't test fit the crank, just measure it, my
beef is now with the supplier. I mean who do you trust these days? This is
my first full rebuild and I do not have the total knowledge to question a
guy with so much experience. I definitely requested a Mk1 crank and got a
Mk2. Simple mistake I guess, but costing me time and money. Next time I will
trust my skills (or lack thereof) with a caliper rather than trusting
another supplier! I am now having trouble getting a refund and am being
pushed to spend more $ doing the mod outlined below.
> oversize bearings if you have to install a used crank that needs
Well. It's like this. I can't find any better crank than the NOS Mk2 crank
(I am in Australia) - this is the third crank in this car in 11 years and I
don't want to risk another failure with a crank thats done 100,000 mls and
is 40yrs old. There is no telling how brittle an old crank is no matter how
under it is. Soo on advice, I am thinking about getting the block modified
to accept this crank. The supplier has done it before, and so has the shop -
but on other engines - any comments? The saddles and caps will need
machining to decrease their width and new thrust bearing surfaces created.
Anyone out there done this mod? Is the Mk2 crank decidedly better, ie is it
worth messing with my Mk1 block to fit it? Any other issues I should be
aware of? I have compared the cranks and there appears to be 130thou wider
on the Mk1 crank Centre and Rear and around 40thou front. Stroke I guess is
the same, how about crankpin relationship to bore centres - did this change
mk1-mk2? I had heard something that the Mk2 shifted it's bore centres
around - did this affect the crank? Argh. I just wish I could find a NOS Mk1
crank. :(
Cheers,
Neil
--
61 A / 70 BGT / 68 CGT/ 56 BN2
URL: http://www.apphosting.com/mgstuff/
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