Crankshaft Identification

[David Morris]

Hi,

Just getting ready for a Javelin engine rebuild to help a fellow new Javelin owner and have a choice of three crankshafts. I would be very grateful for any help on identification.

The three cranks are :-

A. Black-sided square web crank. Big ends at -0.060" regrind and mains at -0.040" One web caries the mark 'CR' in an oval frame. Parts of the crank webs seem to be surface ground but most of the webs have a VERY rough finish, with lots and lots of deep pitting. It almost looks as if the crank has been attacked with shot gun pellets! Overall, it is black in colour. Otherwise, it looks in good condition with almost no wear on the ground journals and where the rear seal sits, there is almost no wear and this surface looks grey in colour, perhaps from nitriding?

B. Oval web crank. Big ends at -0.010" regrind and mains at -0.020" On one side the front web carries the stamp 'U144' and on the rear web '+++'. On the other side one of the webs carries the oval stamp, with 'Laystall' inside the oval. Also, what seems to be a date stamp of '7 58'. Overall, the webs almost seem polished.

C. Oval web again. Big ends at -0.040" regrind and mains at -0.020" No Laystall stamp. However, the oval with 'CR' inside appears again, as in crank 'A'. Overall, the whole crank is grey in colour. Does this indicate nitriding?

If you can throw any light on these three, I would be most grateful. On A and C, there is little signs of wear using my micrometers. Of the three, I would say that crank B shows the most wear, and we are talking 0.004" to 0.005" down on the regrind dimensions. I would happily use A or C to build up the engine, but I would appreciate any tips from the marks on the cranks.

Many thanks,

David