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MG TD TF 1500 - Crankshaft identification

A friend asked me about identifying two crankshafts. I haven't a clue. Hopefully someone here can help. Here is his question. "I was wondering if you might be able to help me with identifying a couple of TD crankshafts that I have? The first one that I have has a number stamped on it 22328 and the other one I have that is in the photos has no markings or stampings on it. I'm in the middle of rebuilding my engine and I was wondering if one crankshaft is a better quality then the other."

Tim Burchfield

Second photo

Tim Burchfield

22528 is the earlier crankshaft, 168557 is the later. While the later is preferred, the earlier can be fine for many miles if the proper radius is ground on the journals.

Have them both magnafluxed and mic'ed to see which is better. The metallurgy is the difference, so you won't be able to tell by eye which the un-marked one is.

Bad journals can be welded back up to spec; a cracked is just that...

Tom Lange
MGT Repair
t lange

Thanks Tom. Very helpful.

Tim
Tim Burchfield

There's a phrase "as rare as hen's teeth." Funny thing is, every chicken embryo has teeth and a long segmented tail, but lose them by the time they hatch.
So how rare are hen's teeth?

What are the chances someone might uncover a forged TD crank? Slim to none?

The first thing I noticed in the first image are the wide parting lines. Just saying.

https://www.chevydiy.com/how-to-build-big-inch-chevy-small-blocks-crankshafts-guide/
JIM N

I know that forged cranks are available today, but who made forged cranks in past years? The second crank must be aftermarket of some sort, since a factory crank would certainly have numbers cast into it, and a forged crank would have no cast numbers, but numbers stamped into it (if any).

Presumably a good machine shop could recognize the difference between a forged and a cast crank? It's obvious I can't, never having seen one!

Tom Lange
MGT Repoair
t lange

The saying is rare as a hen's teeth not embryo teeth. But whatever. Tom, the guy who asked the original question just sent me this, "I took some better pictures of the cranks and I think they are both earlier type cranks." I told him you would be a good source of info on crankshafts. Hope you don't mind.

Regards

Tim
Timothy Burchfield

Tim,

I can relate from personal experience that indeed, the two early cranks are different. At age 18, and with the down payment from my mother, I bought a new TD in 1951 and for reasons that escape me, I decided that, with only 1 year of driving on the car, it needed an engine rebuild. So I proceeded to tear it down, and in rebuilding it, from sheer stupidity, refitted the centre main cap in the reversed position. As one might expect, after a few revolution of running, the crank broke.

So I bought a new crank for all of $121. (Still have the bill! And still have the two pieces of broken crank!) But I noticed the that they both had quite a different ring when struck with a small hammer. Many years later, I learned that TDs (and TBs TCs and all Y-Types) were fitted with cast, nodular iron cranks. The last TDs were fitted with cast steel cranks as were the TFs. However once the stock of cast steel cranks was gone, to fill spare parts requirements, somewhere around 1958, MG contracted ENV to make a batch of forged steel cranks, and for those lucky few who got these, you have a crank for life! Apparently, the majority went to Australia and other commonwealth countries. Can’t tell you about the casting numbers, but it seems you may have at least, the first two.

Buying a new crank today, requires relinquishing your first-born. The regular supplier is Phoenix (https://www.facebook.com/PhoenixCrankshafts/) and as we all know, fetch in the $2,800 range (ouch!!) as they are machined from a solid, forged billet. I believe that the racing crowd, use this crank.

There is hope still for those who run to a budget. Auscrank in Australia - see http://www.crankshaftrebuilders.com.au/Auscrank.aspx are manufacturing nodular iron cranks for our T-Series cars, but they also make the high-end stuff. It all depends on how deeply you can dig!

Gord Clark
Rockburn, Qué.






Gord Clark

This thread was discussed between 14/02/2018 and 19/02/2018

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