Cooper S block & main bearing cap markings

[Cammsjb]

As a matter of interest should original blocks in MK2 cooper S cars have similar markings, if they do are the markings located in the same place on the block as the MK1 cars?

[251 ENG]

All but blocks will be numbered except for very early 1071 and strangely the very last thick flange 1275,s

Most are stamped on the end where water pump is bolted on and on caps

Some later thin flange 1275,s are stamped on tappet cover side of block where petrol pump would be on later mini blocks.

There are also some 1071 blocks that have in stamped on bottom of block near bearing caps .

[Cammsjb]

Thanks for the information,
So is the marking 'Y 106' as shown on the photo that I uploaded previously (page one of this post) the actual block and caps marking for my engine, if it is please can you advise on an approximate date for the engine?

[CooperTune]

Thanks I will check my 64 1071 block and my thick flange one when I get to the shop. Struggling with choice of buying 6 inch rods or surfacing block to use my extra 1071 cranks. The thick flange block came out of a Vintage racer and has four bolt center cap with steel end caps. It blew a head gasket and owner/driver decided to finish the race regardless. Block damage between 2 and 3 will require surfacing a yet to be determined amount. Steve (CTR)

[251 ENG]

Y 106 is not so easy , not got much info , but at a guess could be a late thin flange block , first half of 1969 or if it's a thick flange block would need to know what AEG number cast on back and if it has oil pump prime hole

[Cammsjb]

Hi

The block has a thick flange.

On the rear of the block are, AEG 312, A30D9 above MOWOG and the 1275 plate.

The block is seated on gearbox which has FAXE 2341 and H above SM above 22G1128 above MOWOG.

Thanks

[CooperTune]

OK my 1071 is marked C 3584 and I think I know the build date of the car. The thick flange block has no numbers I can find. Steve (CTR)

Checked heritage cert. 27 May 64 build date. Wonder how close your info will get to that?

[251 ENG]

Steve C3584 on my list is between June 64 and November 64 .

Later rather than earlier , there will be 1071 and 970 mixed in together

[251 ENG]

Close but no cigar

I,ve still got massive gaps to fill in , will add your,s to list

[251 ENG]

Is it the late type casting / not FJ type with studs not bolts ?

[Andrew1967]

Simon, how about C976 - thick flange block

[CooperTune]

It is the FJ casting with studs. Very thin between water pump opening and deck and correct crank engine number tag matches Heritage cert. with 1071 tag on rear of block.

I'm still struggling with paying a dollar per thou. to deck another block or buying 6 inch rods. I have 1071 cranks just hate to shorten a block. The 1360 Cooper S currently in my driver has been with me since 1971 and has been run by me at std, .020, .040, .060 and now 73 mm. I do try and get the best out of them. Steve (CTR)

Someone was asking about gearing, I'm tired of a set up which does all it's work between 2000 and 3000 RPM. It's easy on the ears but there is music above 7000 rpm.

[geroch]

my block is all marked with C 6808, can you go back to the period?

[Cammsjb]

Oil Primer Plug.JPG

Simon re: Y 106

The block also has the oil primer plug if this helps, photo attached.

Thanks

[251 ENG]

Andrew does C976 have just AEG 312 on back or AEG 312 and AEG 634 ?

[251 ENG]

If C 6808 is a 1275 block , Feb to April 1966

[251 ENG]

Y106 , last of early type 1275 thick flange .

I would estimate last 6 months of 1970

[Cammsjb]

When approximately did the use of the early type AEG 312, thick flange 1275 blocks start?

[Andrew1967]

Andrew does C976 have just AEG 312 on back or AEG 312 and AEG 634 ?

Yes, it does have AEG 312 & AEG634 on it Simon.

[geroch]

If C 6808 is a 1275 block , Feb to April 1966

Many thanks, you are very knowledgeable. What a shame, then I do not have the engine of my mini.