Aluminum Head and Valve cover problem

[backfocus]

While working on my car this weekend I have found the oil leak that has been causing me problems. Oil is coming out of the back valve cover on the passengers side. I really new that the leak was in that area, but really thought is was from the thermactor pipe. The valve gaskets are new, replaced them last summer. The bolt that attaches it down won't tighten down, acts like it might be stripped or something. I have always had problems with the one bolt, I have 1/4" x 20 is that the common size for the mustang? Also air rushes in or out I haven't been able to tell yet, would that be a possible vacum leak? Since I have aluminum heads does anyone have the best solution to fix the problem? Very difficult to work back in that corner, or should I take the head off and take it to a machine shop?

Thanks, for everyones help as always.

 

[5spd GT]

I live like 40 minutes from you

I would pull the head, because it does sound stripped. Have them rethread it or helicoil the thread. Good Luck!

 

[ss93cobra]

Agreed. you'll need to drill out the bolt hole and helicoil it.

 

[Michael Yount]

I agree that the best approach is a proper repair to the existing threads. You might be able to do it with the head on the car; you might have to remove the head -- only you can answer that for you.

Since removing the head is a BUNCH of trouble for this relatively small problem here's a suggestion. If in fact the threads are stripped you might try using a sheet metal screw with a hex head that has threads that are just slightly larger than the hole in the head. A steel sheet metal screw with coarse threads should be able to 'grab' the aluminum and hold the valve cover down. There's not much to lose in trying - if it doesn't work, you still have to repair it anyway. If it does work, it's as simple as screwing a different bolt into that one hole. You want the fastener to be no longer than the existing one, and only slightly larger.

 

[backfocus]

Thanks for the conformation, I might try the sheet metal screw for now, until I have time to pull the head off and fix it properly.

And yes 5spd GT we do live in the same area I see you post on here all the time. Maybe I will chat in the Arkansas post sometime.

Thanks Everyone.

 

[5spd GT]

backfocus - Yeah, just join us any time...it is quite large We got to rambling...good luck.

 

[vristang]

Personally, I would not try to tap the head with a sheetmetal screw. The potential for messing up the hole even more is too large.

It may be better to clean the area real well with brake cleaner (using a rag/paper towel) then smear a big glob of silicone over the area. Besides the nasty glob of silicone will help motivate you to fix it right.

Good luck whatever you do.
jason