AJ6 Cylinder Head Bolt Thread Size

The head is 17mm. The thread diam. is 11mm(7/16"?). The thread is course. A 7/16-14 seems to fit nicely. I don’t believe there is an M11-1.75 size, or am I wrong? This is a brand new bolt from Jaguar.

Can anyone shed light on this? Is it possible the head is metric and the thread is SAE?

Can’t speak to the Jag, but old Volvos were that way.

A quick internet search brings up this;

Do you know the original bolts for the AJ6 can be reused twice?
You need to centre pop the bolt head once to indicate the first re-use and a second one when/if the bolt is re-used again.

Yes I do. My question is unrelated. I suspect Jaguar has made a non standard bolt/thread combination. M11 x 1.75 would generally be considered non standard I believe. At least good luck finding bolts or nuts or even finding them referenced on engineering thread charts.

They are in fact M11 x 1.75.