I just finished replacing my valve cover seal and between not paying attention and being a chronic over-torquer, i managed to break the rear left bolt off along with the nut. The rest of the operation went smoothly, no oil leaks even from the left rear corner however I'm worried about not having a nut fastened to the bolt on that corner. Is there anything I can do to fix this aside from replacing the cylinder head, and if no oil is leaking now would leaving it create any potential problems in the future?

 

Tap it with a larger thread and use a new bolt, that's about it.

You'll have to get it out first though.

If it doesn't leak, then you should be fine.

 

so the bolt isn't actually part of the cylinder head? i haven't taken off the cover again so i didn't get a chance to look. in my shop manual it looks like it might unscrew from the bottom for removal but i am not certain until i take another look...

 

I should have specified it's a cap nut that gets screwed down on top of a bolt.

 

So one of those like #16 or #17 that stick up thru the valve cover? If you're lucky, it's broken above that lower hex, so you can still get a wrench on it. Otherwise, drill it for an EZ-OUT.

 

yeah i believe it is like 16 or 17. that means it's also threaded in the bottom as well as the top so i can just remove it and replace it? if so that's excellent news!!

 

Well, this parts drawing doesn't show all the rockers & camshaft & all the other stuff that's in your way. I hope it's as easy as you think!

 

Minimum cross section where torsion shear is most likely is at thread section, so it is very likely that stud is easily removed. Let us know what you find.

good luck

 

YES, to answer all the confusing questions here, if the stud broke off inside the chrome nut, than you can remove the rest of the stud with no problems.