Dougs951S

I have a stripped exhaust stud hole on cylinder number 2. I am going to have remove the header and try to clean the threads up; or timesert it if need be, before I burn a valve. Can the 2-3 header be removed without pulling the studs or messing with the motor mounts? Whats the best way to go about this? Is it as simple as unbolting it from the crossover, pulling the exhaust nuts off, and finagling the header out of the way?

Thanks in advance!

Black51

To be clear, did you strip the nut side or the block side of the stud?

Dougs951S

The block side was stripped when I bought the car, just now getting around to fixing all the small things on the car such as that. It will screw in and bite, but start to turn in the threads just short of tightening up. I've been dreading it because I currently don't have access to compressed air or a good place to work, and I hear the studs have to come out as well. I am also planning on dropping the mid-cat pipe while I'm in there to reweld the Wideband bung because it too is leaking. Again, from the PO's poor weld job.


Oh, and I also realize that the coolant X pipe and possibly fuel rail depending on clearances will also have to be removed.


Ive been reading, ive seen it suggested that I can simply loosen all the nuts and unbolt both header sections from their respective collectors, remove one of the studs on cylinder #3, pull the 1-4 header as loose as I can get it, and then slide the 2-3 header out the top.

Black51

Ya changing the studs is probably a good idea as a start. Fuel rails on these cars seem to be getting riskier and riskier. I've been pondering about possibly getting a new setup with my car being an '86. Might be a good time to get yourself a new one.

The hardware along the exhaust system tends to get pretty stuck in there with all the heat and age of these engines.

Dougs951S

I just changed the fuel rain in my car due to my old one failing and causing an engine fire. I plan to get all new stainless studs wen the time comes to do my headgasket. I really dont want to remove any studs I dont need to and break one off, leaving me with a far bigger issue. I just want to know if this job is possible WITHOUT removing the studs, or by removing just the 1 on the third cylinder. If it isnt broken, dont fix it, and dont break more than you fix.

Black51

So whether you change the studs now or later, what's the difference? If a stud's gonna break, it's gonna break.

I'm not sure if it is possible, and no one else is chiming in yet, but if it were me, I would take them out now and fix the problem once and for all. That way, when it comes time to do the headgasket, I wouldn't be shaking my head saying, "why didn't I do this earlier?"

That's just my 2 cents. Good luck!

Tom M'Guinn

Every car is a little different and some folks Say they were able to get the headers out without removing the studs or jacking the motor. That has not been my experience though ... There is just not enough room between the head and fender for the headers to clear the stud unless you remove several exhaust studs, or jack the motor up, or pull the head off with the headers attached (or hammer back the fender...) It's also fairly tight for purposes of drilling, tapping and getting a helicoil in there, but image it's possible with a right angle dill etc.

gmsracing

I was able to get 2-3 out recently without having to remove the studs or motor mounts. 1-4 required removing a couple of studs in order to pull it. I wanted to inspect the ceramic inserts prior to head removal. After I pulled the head and rebuilt it, I installed the headers on the bench and dropped the head/header assembly in one piece.

Once you get 2-3 out, you should have enough room to run a tap in the bad hole with a wrench/socket to see if the threads will clean up. Just double up the exhaust nuts and then use those to back out the stud. It's a pain with an open end/box wrench but it works. If you do have a problem, usually you will end up damaging the nut instead of the stud as they are copper. I would order some extra nuts as they have a tendency to get rounded/damaged in the process.

Dougs951S

Thanks all for the input. Just to be clear, the offending stud is already out of the car, and the new stud and copper lock nut are in my hand. I have had very good luck cleaning up damaged threads in blind holes on this car so far ( the PO was REALLY ham fisted ) so I feel good that it isnt too far gone, and I should be able to get away without having to put some kind of diamond wire insert into it. I plan to do this job this saturday, so time will tell.

eniac

It's best to remove the studs but as stated all 944 are different. I've had some that come out with only one or two studs being removed and other where I had to remove every single one.

FWIW: Almost always it's the #2 cylinder stud that breaks(3rd one back). I have never had any issues getting the other studs out.

Dougs951S

For me it was the 4th stud back that had stripped. I was able to get the header out the top of the car by removing just 3 studs. it came out in less than 30 minutes, I didnt even have to mess with the water pipe. I ran a tap into all the holes and they all cleaned up nicely, studs threaded back in smoothly so I think I am in the clear. Just going to order stainless studs to replace the ones I removed and a new exhaust gasket, and be on my way. Thanks all.

Black51

Good job! Hopefully you never run into that issue again!