[TR] TR4a Crankshafts...

[Jim Wallace]

Trev,
I have a couple of later TEA20s with the 85mm pistons that I have
restored/repaired extensively.
The main bearings are the same size, and the front oil seal is the same, but
the rear oil seal on the MF crank is the spring around-the-rubber type,
rather than the scroll seal. So you will have to get the aluminium piece
that holds the seal.
The seal is split, so put the split at the top to minimize leaking. (It has
to be split as it couldn't get around the flange for the flywheel.) Speaking
of which, it would be prudent to check the flywheel mounting on the MF vs.
Triumph.
The front could be different too, where the timing gear goes on...can't
recall.
Have a look here:

http://www.geocities.com/wallaces_23/Contents.html

I think I have a MF crank around still, so I could take a look. However my
TR3 crank is now nicely buried in the engine so I can't see it to compare.
Jim

PS You can use figure 8 seals from MF too, as well as big-end bearings. But
the bearings are much cheaper from Triumph suppliers, at least in North
America.
=====================================================

Morning All.....

       In the process of reassembly of a non-IRS TR4A. Told that the
crankshaft had a crack, so talked around, and have settled on a new Massey
Fergusson crank. Can anybody tell me what is required to make this crank the
same as the TR4 model...if anything!

                   Thanx......Trev. hardy..Feilding....New Zealand...