williemon

I finally got the time to fix an exhaust leak on my truck. The manifold has been leaking from the manifold to head joint at the back of the engine. I got a new gasket, and removed the air tube and the manifold. All the nuts and bolts were tight except for one. I had about a month ago tightened them all down trying to locate the leak. I found a stud at the bottom rear of the engine that kept spinning as I tightened down on it. I figured the head was stripped and maybe I could helicoil it. So thats what I was doing now. I saved that nut for last to remove. As I turned it in the direction to remove it, it spun some then got tight. Then the nut itself started turning and came on off. I could see the carbon buildup of where the leak was since it was all around the last (#4??) cylinder. I took a small vicegrip and tried to turn the stud to remove it. I applied good pressure, but did not lay on it, but the stud would not turn. My question is this: Since the stud seems stuck at this point, can I just clean everything up and install the new gasket and install the nuts with no problem, or will the stud most likely fail anyway and I should I just pull and helicoil it? I cant see any threads on the stud on the head side, so it is at least 95% in I guess. Also, one stud screwed out of the head and another one is loose. Should I tighten those in with the vice grips or leave them loose?

growinseed

Since you have the exhaust manifold off I'd take it to a machine shop and have them surface it. If you had a leak it is probably warped beyond tolerance. As for the studs I would put a bit of locktite on them and tighten them into the head with vise grips. They will torque as you work to specs in increments. IMHO the stripped stud, probably won't hold torque specs. and you will have another exhaust leak as soon as you get it back together. One option is to clean all rust, carbon etc. and hold it in place with JB Weld. For this to hold to torque and heat it has to be clean to bare metal. If you don't like this option, soak it with PB blaster,let it sit over night, and go at it with the locking grips you really dont' want to break it off in the head, then go with the hexicoil.
Just a note: make sure you tighten the nuts in increments to torque in a spiral pattern from the center outward.

I just had my 22R apart, If you have a buddy around take off the hood, you get way better/easier access to #4 (back of motor)