Thanks Baz. I'm hoping no…
BTW Baz, I forgot to ask -…
Hi Baz - after a bit of re…
George, do these studs not…
George, do these studs not have different thread form at either end? 26tpi (Cycle) for the rocker box nut, 18tpi (BSW) where it screws into the alloy head. My '56 19S alloy head is definitely 18tpi (just checked the head lying on the bench).
Ian McD
George, do these studs not…
George, do these studs not have different thread form at either end? 26tpi (Cycle) for the rocker box nut, 18tpi (BSW) where it screws into the alloy head. My '56 19S alloy head is definitely 18tpi (just checked the head lying on the bench).
Ian McD
Now I'm getting confused…
Doh! Just realised you're…
Oh well. Back to square on…
I thought all 55's had we…
I thought all 55's had wellworthy heads?
Don't know what that is,…
Sorted! After an interesti…
Previously George Phillips…
Don't know what that is, Dan. Mine has an alloy head. Is that a "Wellworthy"? Does this affect the thread - or rater, the TPI. GeorgeHi GeorgeAs far as I know the alloy head on an ES2 of that era was a Wellworthy head, although the head is aluminium the combustion chamber is iron, hence the name "iron skull". Mine says wellworthy on the side, but am not sure if they all did.Anyway glad you got it sorted, it was always going to be a whitworth thread in my mind, I guess you know the front and rear studs are a smaller diameter than the others.Dan
Thanks Dan. Life is one gr…
The earlier iron head mode…
The earlier iron head models have bolts holding the rocker cover, the alloy head models have studs. I guess the thinking was that bolts could be removed & replaced any number of times from an iron casting but with an alloy casting there would be a risk of damaging the threads so preferable to remove the nut from the stud. It also means that iron head rocker boxes can be removed with the head in situ so the RHS cylinder head sleeve nuts become more accessible. I have never removed a rocker box from an iron head - do the bolts have the same thread as the lower end of the alloy head studs? If not this may explain why George's research led to Cycle rather than BSW. Someone will know.
Ian McD
Once again Ian, that makes…
Previously George Phillips…
Hi Guys, I've found why there is a constant oil mist round the top of the engine. One of the rocker box retaining studs has shed its threads in the alloy head (55 ES2). It's the centre front one at the rear of the exhaust valve. Has anyone any idea what size/thread it is as i intend to fit a helicoil - unless someone has a better idea? GeorgeHi George,I had a similar issue with my 1958 Model 19S. The bolts were a 5/16" BSF (5/16"-22TPI) thread and I got a helicoil kit from Armstrong.Regards,Albert.
So grateful for all your i…
Just checked, Dan, and it…
i will exit stage left
i will exit stage left
Very drole, Baz. Your obvi…
Very drole, Baz. Your obvi…
thanks George
thanks George