At 11:53 PM 3/2/2000 +1100, Neil Cotty wrote:
>.... Firstly I found a 2cm round piece of alloy just sitting next to the
oil pump (motor upside down). I'm not sure where this has come from as I
haven't removed all the pistons yet. My bet is I have lost some material
from around the gudgeon pin boss on one of the pistons (!).
Fairly good guess. About the only aluminum parts inside the engine are the
oil pump and pistons, and in the case of the original MGA parts, the rocker
shaft pedestals.
>....
>The crank is split, like I originally guessed. And what a split it is too.
Clean in half across the first counterweight. The one closest to the front
main, front of motor. It has split from side to side where there are little
squared off indentations. ....
Hey Neil. BTDT. Does it look something like this?
http://www.ntsource.com/~barneymg/grapes/grapes1.htm
>OK so what is my next move besides a new crank, crack tested etc? What is
causing this? Is it that the block could be warped and needs line boring?
The cause is fatigue from old age and lots of revolutions (rotations that
is, not wars, although my MGA engine has been through a lot of wars too).
There's not a lot you can do about the age of the parts. You can now buy a
new crankshaft for the 1500/1600 engine, but the quality of the available
part leaves a lot to be desired, so you might be just as well off using
another old crankshaft. About the best you can do is to get a good used
crankshaft, get it cleaned up and magnafluxed to assure (as best you can)
that it doesn't have any cracks to begin with, and have it redground for
new undersized bearings with the original clearance specs. Good luck
finding another MGA crankshaft down your way. Generally around the USA
there are still plenty of old MGA hulks in the bone yards, but I dunno
about your neighorhood.
Barney Gaylord
1958 MGA with an attitude
http://www.ntsource.com/~barneymg
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