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Rusted Exhaust Bolts

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Have to pull trans out of my sons 95 Impreza 2.2 wagon. The 6 bolts from the exaust are rusted bad. Talking bout the 3 on each side from under the car . Worried if they will snap off if I use a big breaker bar. Is there an easy way of to get them out ??? Dont want to mess up the treads in the heads. thanks

Heat is your friend if possible.

 

Clean those threads out with a wire brush. No sense it trying to pull more crap through that nut than necessary.

 

You can try some juice.

 

Remember either the nut will come off or the stud will come out of the head (hopefully).

 

If it breaks in the head it's not a pleasant day.

If you can, heat it. Then spray with PB blast. Let it soak. Use 6pt socket to get the most grip.

Hopefully it will not be a pita.

Wish you good fortune.

 

O.

Running the engine to temp before hand will heat them up nicely too.

those same studs/nuts on my '95 are also very rusty. but i've had them out a few times, once for the timing belt, once for the clutch, and once for the "new" transmission last year.

 

sprayed them with pb'laster and they backed out. i think that on 4, the nuts came off, while on 2, the studs backed out. no matter, i put em back on that way.

I ALWAYS anti-seize those on reassembly.

 

But I do that with a lot. Like eng to trans bolts, engine mount bolts, heck even the radiator bolts. Just about everywhere. Yea it gets everywhere but should you ever need to take anything apart - especially in the rust belt - you'll be glad you did.

I just never do TC or Pressure Plate bolts. Other than that most bolts get it. Like AC bracket bolts, PB bolts, certainly the tensioners, etc.

Running the engine to temp before hand will heat them up nicely too.

 

X2. Get it up to operating temp and they should come out with little trouble. Some will probably pull the studs out of the heads which is fine. If you really want to, you can get new ones, but usually it's not necessary.

I put a socket and extension on and beat on the extension with a hammer before trying to break them loose. This breaks the rust loose. The stud can actually rust to the exhaust flange, that's how they snap off.

they will most likely come out with the studs. Take the stud/nut combo>put in vice and heat the nut until red hot ( oxy/acy torch) then spin the nut off. If you dont have a torch then you can cut the nut on one side with a sawsall then spin it off with the help of a chisel. clean up threads, add anti seize, reinstall, smile :)

Generous application of Kroil got My 200K mile Exhaust Nuts to turn freely.

 

If You get to the poing of galling the heads, You might want to try a Nut Breaker. It's a small tool that will split the nut, available at most tool vendors.

Might want to make sure you double check the procedure for installing studs in the heads if you don't already. I forget what you've got to do, but I run into people who think you just stick them in and wang on them with pliers to "make them tight." You don't want to strip the stud holes and ruin your day.

 

IIRC you just tighten them hand tight and snug them with a pair of pliers. Maybe someone can chime in to confirm?

they will most likely come out with the studs. Take the stud/nut combo>put in vice and heat the nut until red hot ( oxy/acy torch) then spin the nut off. If you dont have a torch then you can cut the nut on one side with a sawsall then spin it off with the help of a chisel. clean up threads, add anti seize, reinstall, smile :)

 

Chances are the nut comes off with the stud. If so, just replace them. There is a slight chance a rusted stud can take the aluminum thread with it. You can get away with just new hardware if that happens, if you are careful with torque.

 

Thread is m10x1.25 Install the short end of the studs to the head. Thread in the stud first, install pipe, then nuts.

 

You can shop in the HELP brand aisle and either find a pair of 'import exhaust studs', or 3 studs and 2 bolts in the 'GM/Toyota exhaust manifold' kit (get 2 if you need 6 studs)

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