Grr.. broken bolt in head on Jeep

[Michelle Widell]

I've been messing around with this Jeep Wrangler - the exhaust was loud. I took off the intake and exhaust manifolds and found that the rear bolt for the exhaust was broken off in the head (nothing protruding). I read online that this was common, and was covered by an extended 8yr/80k mile warranty (but this Jeep is 10 years old and has 130k miles). So, gotta fix it myself.



I bought some reverse drill bits, some extractors, and had everything all ready to work on it. My boyfriend he'd fixed stuff like that before, so I handed the project over to him. Told him that I found an article online about fixing it, and that the broken bolt needed to be soaked overnight in penetrating oil before attempting to remove it with the reverse drill bits, and that you had to be careful about drilling too deep.



Nah.. he decided to try and drill it out without the bits, and then drill a "little deeper" so he could tap it and give the bolt more bite.



Next thing I know.. there's coolant all over my garage floor - he drilled deep enough in the hole to go through the water jacket in the head.



I didn't say anything (that night). Now he has JB Weld in the hole, with the intentions of letting it harden and then drill it out and tap it. (I bought a helicoil but he refuses to use it..)



What would you do, besides scream...?

 

[Raser x]

Show him to the couch.....



A helicoil wont seal the hole. I believe he is on the right track though. JB weld is amazing stuff. Just make sure that the hole has been cleaned thouroughly with some kind of cleaner (break cleaner works really well). The helicoil may hold after the hole has been sealed. good luck.....Raserx



p.s. give him an A for effort....

 

[Michelle Widell]

Yah, we drained all the coolant and he used brake cleaner on the hole. Trouble is the stuff oozes out of the hole, so that's why he taped some cardboard over it.

 

[Kevin Palmer]

Well, I was going to warn you not to drill too deep. However.......



I am not a fan of JB Weld when it comes to sealing coolant.



You will need to drill into the head far enough to reach the water jacket he punctured. Then the hole will need to be tapped out to some thread. Does not matter really what the thread is as long as you know what it is. I would then get a set screw with an Allen hole in the end of it. Coat the set screw with QUALITY Permitex. Normally blue is good to go with coolant. But in this case I would use Red or Black as they will take higher temps. Since it sits so close to the exhaust port I would think it gets hot fast in that area. Once you install it into the inner hole let it sit over night so it seals very well. Reinstall the manifold. On the hole where you did all the work use a bolt short enough not to press against the set screw.



Option 2: You could do all the above minus the set screw. Get a bolt long enough to pass through the manifold and deep enough into the head to pass thru the inner hole you have drilled and tapped. You will still need to coat it with Permatex.



And the screaming idea you mentioned won't hurt either.... You could having him feeling bad for a good long while. Just think of all the nice things you could get....

 

[Michelle Widell]

The hole is only a little more than a half inch deep, and the stud that broke off in the hole was very short.. So, option 1 won't work. Option 2 is pretty much the plan. I guess I just need some reassurance that JB Weld is going to fix this problem.

 

[Kevin Palmer]

So basically, the exhaust manifold will be held in place by the water jacket????



If your going with option 2. Do NOT tighten too much as you may damage the wall of the water jacket. Tighten ONLY enough to seal the exhaust, (If it will seal).

 

[Todd Z]

I remember on the old jeep v8's the exhaust studs where actually in the water port, IF you removed them water would leak out,,, Wounder if this motor is the same..

Todd Z