Cylinder Head Valley Plug - thread identification

[Enraged]

Anyone know the thread size of the 4 cylinder head plugs? The ones in the plug valley, the 4 big allen socket ones.



I was pretty sure that they are 5/8 BSP (parallel, not taper), but now I'm doubting myself. I've measured the very back plug to have a pitch of approx 1.8mm, so that is 14TPI, which lines up with 5/8 BSP (1.814mm/14TPI).

But the major diameter (OD) of the threads is 23.75mm. But in all the charts I read, 5/8 BSP should have a major of only 22.4mm. So maybe it's M24x2?

I'll go to a local hose shop to confirm it, but I was hoping someone might have the easy answer for me.

 

[trofimovich]

Thread metric 27x1.5

 

[Enraged]

Thanks for checking

Are the ones without the bolt hole a different size? Because M27x1.5 is nowhere near the size of the one with the bolt hole that I have in front of me.

 

[eraezer]

EDIT: I removed my text as it might be incorrect

 

[trofimovich]

Sorry

 

[Enraged]

I bought an M24x1.5 drain plug yesterday and it threads in perfectly, so confirmed it is that size. Thanks!

 

[trofimovich]

My pleasure.

 

[Bru]

When I put these back in I use a little bit of Prematex Ultra Black silicone to seal for oil seepage.

 

[Enraged]

For a new product we're working on:

 

[MDCmotorsports]

For a new product we're working on:

View attachment 80721

Looks amazing. Anchor points for 2jz batch coils???

 

[Enraged]

Looks amazing. Anchor points for 2jz batch coils???

Not 2jz, but yes for a individual coils on a billet bracket.