Carb connecting studs

[chrisx1]

can anyone please tell me the thread sizes for the carburettor studs. I need to re-tap the head and re-thread the studs both to the head and carb.

[Spaceman]

Part 68-0018: 5/16" dia with BSF on one end and BSC the other. Length seems to differ among suppliers but ~1 3/8".

[chrisx1]

Does the BSC thread into the head?

[Spaceman]

The coarse thread (BSF) should go into the soft aluminium of the cylinder head. However, I would get a 5/16" BSF bolt and double check that it appears to screw into cylinder head just to make sure a previous owner hasn't changed the thread!

[chrisx1]

sorry Spaceman is that a typo? bsf is fine bsc or bsw are coarse.

[chrisx1]

I've just had a thread checker on it and it seems to be 22tpi on the end that came out of the head which seems to equate to 5/16' BSF.

[Spaceman]

The coarse is 22 tpi BSF and fine 26 tpi BSC

[chrisx1]

Ok, great thanks again for your help. Ive ordered a 5/16'BSF tap to clean up the head threads. and ordered new studs, as the original ones are buggered.