Exhaust studs gone wrong!

[gman991057]

Hey guys I just recently bought my 90 tsi which had a slight exhaust leak when i bought it coming from the head to exhaust manifold area. I decided id give the exhaust nuts a little bit of torque to try and seal the leak when like many 14 year old dsm cars with rusted studs the first just broke right off. I stopped right there knowing id have to spend some time in the garage and swap some new studs in. While removing the remaining studs i ended up breaking 2 others and after failing to easy out any of them I dremeled them out making new holes in the process. I ended up tapping all but the top right stud into the head but while filling the radiator with water to try and get a good idle out of the car water started pouring out of the studless hole. I imediately thought i may have drilled in too far with the dremel but after thinking im not sure whether or not water is coming out only because there isnt a stud there to block off the water. As of now my plan is to take the mani back off and finish the studing job while adding a bit of JBweld help along with the new stud. I am looking for as much experienced advice as possible, i am still but a determined newbie in the dsm world, i love my car and i would like to accually get it registered and insured for the FIRST time!! Please help a fellow single car garage technician Thanks -Griff

 

[Quasimondo]

I dunno, if you drilled far enough to have coolant come out of that hole, then that head seems done for. Might want to start shopping around for a new cylinder head.

 

[doodie]

You probably did hit the coolant part of the head. They're actually really close to the studs, thats why most people don't drill them out.

 

[wyominghotwheel]

i would have to agree....i too, would start looking for another head. hotwheels

 

[Catbox_95]

If you have at least some thread-bite left, I would just JB Weld a stud in there and go. If that doesn't work, look for a new head, but it's a quick, cheap and easy fix to see if you can get by with your head.

I had the EXACT same problem with my exhaust studs. One broke, then while taking them all out, 2 more broke. At $12.50 each, I just had a machine shop take them out, and now after seeing the headaches you're facing, I'm glad I did!

 

[sjwelna]

i would have to agree....i too, would start looking for another head. hotwheels

Yup, start shopping. You can probably find a new head (stock) for about 150-200 pretty easily if not cheaper.

-Steve

 

[92redman]

You could probably get away putting sealer on the threads of the stud. Chrysler has a few engines that have bolts running into passageways, you just have to use sealer on the threads so they don't leak. It will have to be a high temp sealer though.

 

[gman991057]

Thanx to all for there opinions. I wen to my local shop and picked up a heli coil set where you have to dril the holes bigger then thread the holes with a certain tap bit that the heli coils thread into. all the heli coils are are metal boots rather that thread into the hole and in turn create a new thread that the inside of the heli coil boot has. You can buy all different sizes but for the stock dsm sized studs you would get 8mm with 1.25 thread sized heli coil. Your studs will screw right into the heli coil that you've threaded into the holes. To help seal the radiator fluid I also used a high temp. sealant around my heli coil and studs. So far i've had the car idling for a long period of time and so far no leak. I have yet to drive the car due to the fact that it decides to throw a code for what seems so far as no reason at all. This problem of mine will be posted in another thread. Thanx 4 the words of wisdom. -Griff