Damaged thread on head

[TheHood]

I don't know when /who did it but the thread on the inlet side of my head circled in the picture below is chewed up quite badly and now the bolt won't tighten up.

I know it's not causing any air leaks, but it bugs me to know it's not right.

Would it be ok to tap it out - preferably to M7 as that stands a chance of wiggling through the hole on the inlet manifold?

On the face of the head it looks like it shouldn't be a problem, but I wanted to check if anyone knew of any water / oil channels running near by to be cautious of.

Thanks

( apologies to any engineers reading terminology like "hole" in this thread )

 

[vocky]

I recently increased them all to M8 from M6 for a sc head, so M8 might be worth a go

you will probably have to remove the metal insert on the manifold

 

[TheHood]

Thanks Vocky

Jon at Courtenays said the 2.0l version of the head uses m8 studs, but I wanted to be sure before I do anything as potentially damaging as drilling my head.

 

[FLD]

Why not helicoil it?

 

[TheHood]

Why not helicoil it?

Because I did'nt know what the hell a Helicoil was!

Mind you ten mins reaserch here http://www.helicoil.in/helicoil.htm and here http://www.roadstarmagazine.com/modules ... le&sid=233 and it all becomes clear

Thanks

 

[FLD]

Ah, looks like I'm a bit rough with mine then! Most engineers charge around a fiver for a helicoil repair.....errr so I've been told