Dizzy clamp

[el torro]

Anyone now nut size on end of clamp,I am struggling to get it loose to adjust timing

[Chancer]

From memory, and its d?cades old the size is either 3/8" A/F or maybe 7/16" A/F, that was the double ended spanner that I used.

You said "nut", you do realise that you should be using the spanner on the hex head bolt and not the square captive nut which wont want to turn and is an odd size hence my suspicion.

[vincereynard]

As Chancer states - 7/16th for both.

[alan.barker]

For fine adjustment of timing you undo the screw that holds the clamp to the block. The slot in the clamp is for this.
7/16 AF

[el torro]

Many thanks for info and photo's,takes all guesswork away