23 replies to this topic

[minilee94]

I just found a head on eBay with same thing sorry if its your head anyone on here

[bmcecosse]

I wonder if these are the correct collets for the caps - the angle changed over the years - along with various other modifications. Get a spring compressor (not expensive) and open them up for inspection - and let's see some pictures of what you find.

[minilee94]

Okay so I need pics of collets and caps yeah il see of I can borrow a compressor thanks

[MRA]

Theres nothing wrong with your head, the caps are for single collets and that is what you have. However it is always worth a chack if it is off... But DO NOT mix up the parts, keep them together and make sure they go back in the correct position, ie valve no1 (nearest thermostat) goes back into no1 etc

[minilee94]

Okay I won't remove valves just springs and collets as I might replace springs while I'm
At it

[ACDodd]

Agreed, the collets are fine, there are 2 types fitted to the 1275 head, the early type shown here that do not perfmit valve rotation, and the later triple collet, type which do allow valve rotation. The later type do no have a gap as they are designed to butt up against each other and the hole formed int he middle isbig enough to not clamp the valve. The earlier type have to have a gap as shown are they would not clamp the valve tight.

AC

[minilee94]

Okay thanks ac Dodd just wondering what ones are better the ones I have or the closed type

[MRA]

The ones that you have are best for reliability of the valve, the triple groove is better for the seat as it allows the valve to rotate and maintains seat quality for longer

[minilee94]

Okay thanks