e36 m42b18 sparkplug port size?

[Venom]

Hi All,

As per title really just curious to know what this measurement is as I'd like to buy a compression tester.

I've had a look through my Bentley manual and also googled with no success.

If anyone could help?

Many thanks

[DesktopDave]

Welcome to the 'club! 5/8" socket IIRC.

It's the easy questions that stump me, LOL. We only get two plug sockets over here in the good ole' U.S. of A..

It has to be either the 5/16" socket (AKA "the little one") or the larger 5/8" plug socket (AKA "the bigger one") over here. I had to special-order a 14mm motorcycle plug socket - nobody stocks them here!

I'd seriously consider the types with the long t-handle, as the plugs are deeply countersunk into the head.

[Venom]

Thanks for the reply and welcome.  Do you know it never dawned on me to check the size of the socket i use to remove the plugs!  And after checking you are indeed correct, 14mm