HI Everyone.

I have to replace the exhaust system on the Goat.  On the drive to the nationals last summer the Flowmaster Symphony Orchestra began sounding more like Spinal Tap.  It's a really old system booger welded together so I'll be glad to see it replaced.  I've ordered the parts to replace it myself.  A place opened up near my house that rents out their hoist so I'll do the work there.  I was checking the exhaust manifolds, and it looks like the pipes connect to the manifolds by nuts and studs.  I'm a little concerned because knowing my luck a stud will break when I try to remove them.  Any advice on removing the nuts without breaking a stud?

Thanks Everyone

Use lots of penetrating oil first and then some torch heat to get it red hot.  There is also a "nut cracker" tool that sharply splits the nuts for removal.

  I'd remove these mild steel studs and go back in with hardened studs from ARP.

Rick

As has been indicated...

Use lots of penetrating  oil...Starting a couple of days before attempting to loosen the nuts/bolts...If you're going to replace the entire exhaust system from the exhaust manifolds back...I would highly suggest that you Cut the head pipes off as close to the manifolds as possible....To get them out the way...Allowing you to have more clearance and a straight shot to use the tools sockets/extensions..And or wrenches/tools that you intend to use...So the tools will fit flush (not on an angle) on the fasteners...Also be Sure to use (important) 6 point box end wrenches And or sockets...

If the manifolds have one stud/nut and one Nut/Bolt at the flanges....If the nut and bolt are frozen....just go ahead and cut or ring off the bolt and be done with it...If the nut is frozen on the stud try slowly working the nut back and forth (It may help it loosen it) Sometimes the stud itself may loosen in the manifold with the nut frozen on it and come out together which is good...If not heat the just the nut until it is red hot...Then using a squirt bottle with cold water in it...aim the cold water stream at the stud once the nut is hot...The cold water concentrated on the hot stud will cause it to shrink....Thereby allowing the hot expanded nut to easily come off Hopefully without breaking/galling the threads on the stud...

If you do wind up having to replace the stud...I highly recommend that you Do not use a hardened stud to replace it...Because hardened studs in that particular application are very prone to breakage Due to all of heating/cooling cycles they are exposed too...(changes the molecular properties of the steel making them very brittle over time)... If/when the hardened stud ever breaks...It will nearly impossible to remove/drill out...Compared to soft studs...

TLBT..

Edited January 30, 20242 yr by TWO LANE BLACK TOP

Thanks for the tips.  The engine was rebuilt a few years ago so there is a possibility the nuts will unthread.  I plan on carefully cutting the old system out.  I'll be sure to get replacement studs.  Luckily the car will be on a lift so working with the studs will be easier than lying on my back.

So what are you replacing the old exhaust with?

I'm replacing it with a stock system and a new set of Flowmaster Super 40's.  I thought about installing the factory correct mufflers but we like the Flowmaster exhaust notes.

On 1/30/2024 at 7:00 PM, reveredGTO said:

Thanks for the tips.  The engine was rebuilt a few years ago so there is a possibility the nuts will unthread.  I plan on carefully cutting the old system out.  I'll be sure to get replacement studs.  Luckily the car will be on a lift so working with the studs will be easier than lying on my back.

I think everyone has covered the needs of getting the studs out quite well. I would just add that you might consider using 316 stainless steel studs, nuts & lock washers. 316 stainless will never be a problem to get out ever again. This is what I always run on my exhaust or high heat source application, even my cats. 
Whether you chose to do so or not I would advise retapping the holes out to clean out any debris. If you chose to use the 316 you may have to make your own studs from longer bolts, studs are not necessarily that available. You can also use 304 stainless, but 316 is far superior for corrosion & heat oxidation.