Help required deciphering bearing codes

Post by **leyther8008** » Sat Mar 08, 2008 2:46 pm

Hello all
I hope somebody can help:-
I,ve just pulled a main and a big end bearing from an engine I,m re-conditioning and the shells are marked

Big end:- G in a circle, A in a circle, KM
12A630
Main:- PV in a circle 4499 (one end of shell)
AEA 471 (other end of shell)
So whats the secret to unlocking these codes?
My question is what size of shells do I order as a direct replacement? crank not worn so I just intend to replace shells as a precaution.
As usual any help most welcome
Regards
Bern

Post by **les** » Sun Mar 09, 2008 9:44 pm

Couldn't you just measure the diameter of the journals and, presumably you know what engine it is, report your findings to a supplier. ie; Std, 20thou under, 40thou under etc? Undersize bearings are usually marked.

Post by **leyther8008** » Mon Mar 10, 2008 8:03 am

Would if I could but as the crank is still in the block I couldnt measure the mains and I havnt got a 1-2'' Micrometer, hence request for bearing codes

Post by **les** » Mon Mar 10, 2008 6:59 pm

ahh, with you! 12a and aea are leyland number prefixes, good chance they are standard, but of course you need to be sure.

Post by **leyther8008** » Mon Mar 10, 2008 8:00 pm

No worries I,ve an engineer on the case, a friend of a friend who can internally mike them for me then I can deduce the size from the tables in the workshop manual.

Post by **Alec** » Tue Mar 11, 2008 6:48 pm

Hello 8008,

unless there is a 10, 20 etc (maybe 010, 020) then they are standard.

I don't know the meaning of what you quote but they are manufacturers references. Nothing to do with size.

Alec

Post by **leyther8008** » Fri Mar 14, 2008 3:56 pm

Thanks for the info Alex
I,ve only just managed to get back onto this website, I have found out the hard way they are standard, a set of -10s locked the crank solid, so I,ve sent for a set of standards another 14 quid wasted! I must have the only minor engine with standard shells after all these years!
Bern

Post by **bmcecosse** » Sat Mar 15, 2008 12:32 pm

The shells will indeed be standard if not marked as oversize (to suit undersize crank). The G and A are for Glacier and Associated Engineering and the KM is for Kilmarnock where they were made - and where I worked for a while in the Materials Unit! The PV is probably for Vandervell. The other numbers are indeed BMC part numbers.