12mmx1.25? 1.5?

 

did the search (first archival dig of mine on the new board) found a thread.. yet only stayed confused.

 

 

Thanks guys

 

Caleb (the soobie nerd formally known as Subrina7)

And you are wanting to re-tap which threads in the head?

(should have been clearer) the head bolt threads in the block.

It is M11 x 1.25.

 

A fairly uncommon size......

 

I just ordered the tap and die from MSC for about $20.

thanks Toybuilder.

 

Ended up doing 3 7/16 coarse heli coils.

 

Problem I encountered at that stage was keeping the drill plumb to the short block surface- 1 out of 3 seemed straight when finished, placing head on was tight since 2 studs were off a hair facing either way.

 

For furture reference, any tips on keeping that drill more plumb? I did not see a real practical wa to set up a guide.. tried to check against a square but that became irrevelant once the metal started curling out.

Somewhat related . . .

 

To replace the O2 sensor on my '93 EA82, and not having the special tool, I had to remove the upper and lower heat shield around that junction, where the two headpipes join. To do that, I had to unbolt the headpipes from the heads to drop the whole pipe assy down far enough to remove the upper junction heat shield.

 

Naturally, three of four studs came out of the head, instead of the nuts coming off of the studs. Also naturally, the studs galled coming out, dragging some aluminum threads with them.

 

The holes are 10mm x 1.25mm pitch, which, if you're familiar with the metric stuff, is the "middle" of the 10mm coarse/medium/fine thread pitch smorgasbord.

 

Fortunately! I have access to a 10mm x 1.25 Helicoil set This is not a terribly common size. Astoundingly, I also have the correct drill size to prep the hole. And, there's actually room to manoeuver the drill under there, unlike most in-the-car stripped hole repair jobs.

 

And my local parts store actually had the correct 10mm studs, correct length and everything.