From: British Cars Digest #1374 Thu Sep 22 16:10:17 MDT 1994
>> Date: Thu, 22 Sep 1994 12:20:00 EST
>> From: "Roger Garnett" <@cornell.edu>
>> Subject: Re: Seeking pointers for painting/reinstalling MGB engine
>> July 4 1993, on my way to Chicago in my 1974 MGB, I threw a rod.
>> Turns out that I also cracked my crankshaft...
>> local machine shop ... welded
>> the crankshaft back together, and then machined it.
>Wha-hoo! I don't think I've ever heard of someone trying to repair and use a
>cracked or broken crank! The crank is a highly stressed, critical item. One
>might consider this on a rare, vintage machine, which gets low use & loads,
>and would be quite expensive to find or make a replacement crank for. For an
>MGB, new and used cranks are quite readily available. It's not worth the
>potential damage (shredding the whole engine), should the crank come apart.
>If anyone has experience otherwise, I'd like to hear about it! About the only
>damage repairs I'm aware of for cranks (outside of regrinding, undersize) is
>surface welding on scored bearing journals to build them back up, and then
>re-grinding.
IT CAN BE DONE!!! When I read this I though I had heard something about
welded cranks, but I dismissed it. Well, last night in the "reading room"
I found an article on the Great American Race of the last year.
For those in the dark, the Race is a cross country rallye from one US coastal
city to another in vintage cars. It usually atracks media attention in that,
for some reason,the average Joe Homeowner doesn't know that cars that have
already outlasted his newbie could perform such a feat.
Last years race had a couple Bently's (REAL Bentlys!) a couple t series MG's
(one TA?) some racecars and a FIRETRUCK, which was a veteran from other races.
Well, it seems the firetruck broke it's cranck shaft somewhere in the mid-west.
Since the local NAPA was out of American La France V-12 cranks it was WELDED
together!!!! And finished the rallye!!!!
However, I do agree that something as common as a B, where you can build your
own from new parts, should have a new crank. It's not worth the trouble.
Another way to build up cranks is chrome. When we had the crank from our
Riley built up the shop offered two options: spray welding and chroming, we
opted for the spray weld.....mabye when/if we get it back together I can
offer a longevity report.
First day this week w/o rain, and the sun is out too!!
Great for projects!
Kilroy
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