164 TS oil drain plug

What is the size of this. I've changed the oil before without any hassle
but for the life of me cant find the correct allen key. 12mm is a tad too small and 14mm way too big. Maybe Im just getting addled in my old age.

Have you tried a 13mm?

Interesting choice of words:tad too small and way too big. If plug is metric then it will be 13mm but if 12 is a tad too small then it could be 1/2" (12.7mm). This would of course mean some other plug has been used - worrying if it has as the threads might not be quite the same.

Does the plug leak or weep at all?

I´m quite sure it should be 12 mm, original plug.

i ve chanced my oil on my 164 and it was a 12mm allen key

Ok I'll stick with the 12mm then its maybe just a bit worn now having been done numerous times. A 13mm plug might be just the job if they made one

May be it's tapered? You can buy the correct allen socket from Halfrauds.