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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - TF1500 Crankshaft

Can anybody explain the note from the TD/TF Manual reprint (the blue book, soft-cover): it states on
page A 24 "Grinding the Crankshaft" that "on XPEG engines the crankshaft cannot be reground, exchange for p/n168557".
Since the c/s's on the xpag and xpeg engines are dimensionally identical (I assume), this could indicate a difference in material? Nitrided? Or was BMC just trying to sell spare parts?
Any information on this issue would be appreciated.
T W Moore

I believe XPEG cranks were of better (EN16 I believe) material than earlier XPAG cranks, and were nitrided for hardness. I have had XPEG cranks re-ground before, but not more than .020. What is critical is to get the proper radius on the journals and balance carefully (ideally to within 1/10th of a gram) because these cranks DO break, especially at the first journal. I've seen guys have everything magnaflux fine and properly rebuild their engine, and break a crank within a few thousand miles for no good reason - or no obvious one. In the olden days it must have been a lot cheaper to get a new crank than to have the old one ground and heat treated, which may be why MOWOG notes the need for replacement.

1500 blocks are getting hard to find so be careful, but a good used crank, properly magnafluxed, ground, radiused and balanced, ought to be OK.

Tom Lange
MGT Repair

Tom Lange
MGT Repair
t lange

Interesting topic, for those thinking about hopping up their XPEGs. What with the new cranks produced today? Do we really know that they are better than the old ones? Generally speaking, aftermarket parts seem to be of very variable quality these days. My last experience being nuts ment for a highly stressed area on the car, but seemingly made from melted down beer cans or old mazac door handles or whatever.

If one was to purchase a brand new crank today, where would one look to part with a considerable amount of cash in exchange for some serious peace of mind?

regards,

Jan
JE Kristoffersen

Moss sells a forged crank that is certainly a step up from MOWOG (forged in the UK and machined here in the US), and MOLDEX has the very best billet crank.

I have not been successful in finding an affordable crank manufacturer, even when ordering a run of 20 at a time, for T-type engines.

Tom Lange
MGT Repair
t lange

Tom I think the supply of forged cranks ran out. Last time I looked they now list a billet job.
MG LaVerne

Good to know - thanks LaVerne.

Tom
t lange

Just to be clear, a billet is technically a square chunk of metal, and a round is just that. But billet has come to mean a crankshaft that is cast as a block of metal, and then fully machined to a finished crankshaft. This ends up being a more expensive process, due to the need for total machining. This process can also use a higher grade of steel, because it does not need to be hammered into shape.

A forged crankshaft is one that has been cast and hammered into the rough shape of a crankshaft, and then finish machined. Surprisingly (even with the availability of CNC machines), this process ends up costing less, when spread over a large run. But the choice of materials is more limited, since this product must be forgable.

Each has its advantages, and I would not hesitate to trust both of them.

Tom Lange
MGT Repair
t lange

This thread was discussed on 19/12/2013

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