350x header pipe removal question

[swampthang]

I'm wanting to get a new exhaust system for my 85 350x, prolly a black or chrome DG (yes I know there not the greatest pipe out there but they have to be better then the 85 stock exhaust system) I have a consern about getting the nuts off of the exhaust studs with out destroying them( they are bad rusty) Does anyone have any tips or tricks to get them off? They seem really awkward to get a socket or a wrench on them. What have you guys used? Is it better to try and remove them when the pipe is warm? I plan on using alot of liquid wrench for several days before I give it ago.

[Dirtcrasher]

Oxy Acetylene, liquid wrench does nothing............

[ctbale]

yea, if your lucky the stud will unscrew out of the alum head, stud and nut on mine usually just stay together, then just screw in a new stud. I use the silver anti-sieze on the stud/nut. like DC says, get that alum hot hot hot, I smack the stud like a nail just to shock it a bit too!

[Thorpe]

^^ As stated above works... But what I have come to discover... The worlds best way to remove a rusty nut from an exhaust stud, is a dremel. Using a small cutoff wheel, cut the side off of the nut, ever so carefully until it splits right next to the stud... Then you can back it off with a pliers, and reuse the studs with fresh nuts and high temp anti-seize compound...

[swampthang]

Well, bad news I think I screwed up bad:( I tryed to unbolt my header pipe and one stud cam out with the nut rusted on and the other 3 broke off with about a half inch of thread sticking out. Where do I go from here? Should I try to weld a nut on and try to back the studs out? If I use heat do I try to heat the stud or the head? I know the head is aluminum how much heat is it going to take? Im very flustrated with myself my 350x is my most prized possession hate to think I screwed it up

[2Tim215]

I would place a nut over the worse stud flush with the head. Be sure to get the stud as clean as possible before trying to weld the nut on and use a clean nut. Make sure you have good penetration to where you see the top of the stud and nut have somewhat "puddled" together in the center. I would wait a few seconds and then while it is hot back it out. That should do it.

[Dirtcrasher]

I'll eat a head on you tube if it works......

The worst thing is when the studs come out, they normally do not leave a clean hole and need a helicoil to tighten down well again; Of course at this point it's best to go stainless.

You may have to take the head off, I have seen the casting bosses snap off when removing a stud rather than milling/drilling it out.

Worst case scenario, take it out and send it me, I've done dozens of them now.........

[fabiodriven]

I can't believe people are still doing this. Time after time. Reminds me of lemmings...

[Bryan Raffa]

I'll eat a head on you tube if it works......

The worst thing is when the studs come out, they normally do not leave a clean hole and need a helicoil to tighten down well again; Of course at this point it's best to go stainless.

You may have to take the head off, I have seen the casting bosses snap off when removing a stud rather than milling/drilling it out.

Worst case scenario, take it out and send it me, I've done dozens of them now.........

he should have listen the first time.... ahhh well,, guess whats next... snap it off flush,,, and HELP!!!!!!!!!!!!!!!!!!!! LOL

[2Tim215]

I can't believe people are still doing this. Time after time. Reminds me of lemmings...
If you are referring to my suggestion it works fine. I guess it would depend on your welding skills. I use a Hobart Mig and haven't had a problem yet. I suggested trying one first so if he didn't have the welding skill or it didn't work then he could try a different route. Its a lot easier trying one stud than pulling the head.

[Bryan Raffa]

if he got the nut cherry RED he wouldnt have to weld ... is his point! and mine... and a few others...conceder yourself lucky if it worked..I do it everyday on dodge exhaust studs...

[Dirtcrasher]

^ YES, tell that to Mr. Hobart...............

I have 20% luck with that process and never in a head.

[2Tim215]

if he got the nut cherry RED he wouldnt have to weld ... is his point! and mine... and a few others...conceder yourself lucky if it worked..I do it everyday on dodge exhaust studs...
I agree with that 100%. I posted after he broke them. The torches would have worked had he went that route. I was surprised he went on to the other two after the first one broke. Hard to say what tools he has on hand???

[fabiodriven]

If you are referring to my suggestion it works fine. I guess it would depend on your welding skills. I use a Hobart Mig and haven't had a problem yet. I suggested trying one first so if he didn't have the welding skill or it didn't work then he could try a different route. Its a lot easier trying one stud than pulling the head.

I was not referring to you. I was the manifold guy at a custom exhaust shop for 2 years. I've probably done the exact process you described hundreds of times. With the cast iron heads you can get away with removing a stuck stud and cramming one back in there. The 350X head is aluminum. It's more than likely the stud is going to take some aluminum with is on its way out, if he can even get it out. Or he'll break out the drill and drill a cock-eyed hole. Then it still needs to be heli-coiled. At the end of the day, the head should come off. I've personally seen some heads that people tried to fix on their own before sending it out to the expert and it makes life harder for everybody and destroys parts.

[RIDE-RED 250r]

Whatever you do, do NOT put an oxy/ecetylene torch to the aluminum head! When you put that kind of heat to aluminum, it melts very fast, almost like solder in a propane torch flame, (dont ask how I know). Aluminum's melting point is only about 700 deg farenheit, the oxy/acetylene flame can reach temps over 5000 deg farenheit.

[2Tim215]

I was not referring to you. I was the manifold guy at a custom exhaust shop for 2 years. I've probably done the exact process you described hundreds of times. With the cast iron heads you can get away with removing a stuck stud and cramming one back in there. The 350X head is aluminum. It's more than likely the stud is going to take some aluminum with is on its way out, if he can even get it out. Or he'll break out the drill and drill a cock-eyed hole. Then it still needs to be heli-coiled. At the end of the day, the head should come off. I've personally seen some heads that people tried to fix on their own before sending it out to the expert and it makes life harder for everybody and destroys parts.
I know people use different methods. I know some heat them up on exhaust manifolds and actually use wax. It acts like solder to copper and gets drawn in while the stud is hot lubricating the stud at the same time. I'm not a expert by any means but have been welding since 1992 and it sounded like swampthang had a welder on hand. Drill bits that are hardened steel make it VERY difficult to repair if they break off inside which can happen easily using that small of a bit. Again, I suggested to just try one to see if it worked for him. If not hopefully he can remove the head bolts okay and have it repaired.

[2Tim215]

Whatever you do, do NOT put an oxy/ecetylene torch to the aluminum head! When you put that kind of heat to aluminum, it melts very fast, almost like solder in a propane torch flame, (dont ask how I know). Aluminum's melting point is only about 700 deg farenheit, the oxy/acetylene flame can reach temps over 5000 deg farenheit.
Ride-red, the torches were suggested before he broke the studs where they could have been used to heat the nuts that hold the flange in place and wouldn't have been used on the head itself.

[RIDE-RED 250r]

Ride-red, the torches were suggested before he broke the studs where they could have been used to heat the nuts that hold the flange in place and wouldn't have been used on the head itself.

I hear ya, I just wanted to make sure he didnt try to use oxy/acetylene to try and heat the head to extract the broken stud...

Too bad he didnt try to heat the nuts, even with a propane or MAPP gas torch. Might have worked. My little MAPP gas torch has impressed me many a time for freeing up a seized nut or bolt.

[fabiodriven]

If not hopefully he can remove the head bolts okay and have it repaired.

I've never had a head bolt not come out. Exhaust studs break 75% of the time. You do it your way, I'll do it mine.

[2Tim215]

I'm not disagreeing with any of the other suggestions, guess mine was the only one that didn't go over well! Just trying to help swampthang get out of a jam!

[2Tim215]

Here's a link for two studs that used the welded nut method that worked on a Honda motorcycle. The video is grainy but you can see he didn't have much stud to work with. The threads seemed fine on the re-install. I would have used stainless replacement studs though as was suggested above. I'm getting ready to do one of my 350X's and have the OEM studs but plan on using stainless instead. IF you go this route be sure to use plenty of lubricant going back and forth a bit before removing all the way. Hope this helps,
http://www.youtube.com/watch?v=m0uxnWzDFI8

[swampthang]

Thanks everyone for there opinions and help. Bonehead move on my end. Should have found someone with a torch but my studs where still in bad rusty shape. I'm not going to try and remove the broken studs from the head myself I dont want to risk damaging the head itself. I've got to finish up my Tri-z project first before I start tear down on another machine. When it comes time to fix it I'll shoot you a P.M. Dirtcrasher, your work is impressive to say the least. I dont believe my local machine shops would have much experience with a 350x head.

[swampthang]

here's a pic of one side. I think it could be an easy fix for someone with the right tools and know how.

[RIDE-RED 250r]

Yep, smartest thing you can do at this point is send it to DC while there is still some stud left sticking out.

[Ironbnder]

I think we will all agree that there is more than one way to skin a cat. Your way may work for you and anothers way may work for him. Telling a man that is borrowing a torch to heat it up is easier than him knowing when to heat, where to heat, when to cool, when to spray it, when to loosen it and when to tighten it back up abit before loosening again. That is what seperates mechanics from parts changers.

And I am in no way talking about you Swampthing, just a general statement about working on rusty crap.

[Dirtcrasher]

One thing allot of you are missing: At some point Honda knurled the end of the studs that goes into the aluminum head. I don't know when or what serial number it started at, but it ruins the threads (in the aluminum head) on it's way out. It is meant to stay in the head......

I don't care how much sticks out, I mill them flush, drill them out and helicoil them. I've done many many of them and not one person had an issue once I put in stainless steel studs.

I never try to get them out, it can ruin the whole head and based on what I've seen, allot of people try to remove them not understanding the issue at hand.

Order some new studs and you will see the knurling. Other model head studs are just plain threaded studs that you have a chance of removing AOK.........

[2Tim215]

I have the four OEM studs for one of my 350X's and mine aren't knurled. That would certainly make sense as to why some of the factory originals are hard to remove though. Steel and Aluminum aren't friends over time thats for sure. I'm certainly not questioning your work. Good to have someone who can help other members with stud replacement. I'm sure a lot of us are limited with our tool collection and certain abilities, I keep building up my metrics. I just added the 27mm impact socket today for my clutch. Here's a photo of one of the studs out of the package. Both ends are tapered properly and a flush center.
http://i130.photobucket.com/albums/p242/Avon2day/stud1.jpg