7.5L (460) exhaust bolt question...

[Rick W]

If the bolts feel like they are too tight or may break I just fire up the torches and blow the heads off. Once the manifold is off you can get a set of vice grips on the stud and it usualy comes out pretty easy.

A couple thoughts, maybe refinement. If you have a torch, even a Home Depot plumbing propane toy, get the nuts and end of the studs red hot. When you put the wrench on them, don’t just crank, gently but firmly wiggle them back and forth. Why? You may be able to break them partially free in the rusty hole, but wiggling will break up all the frozen spots and allows the motion and tight space between studs and nuts to “powderize” the rust to talc-like fineness, rather than bits. I’m not sure some of those words are actually words, but you get my idea.

If the nuts are very stubborn, you start with penetrating oil (not wd40) and let them sit, then you can heat and wiggle, let it cool down, and then do it all again, maybe several times. I’ve never had it fail, but it takes time (but not as much time as snapping one off!).
QUOTE="bobbywalter, post: 1748751, member: 439"]
Cause that don't necessarily work around here. Sometimes they grow together. And I just smash them with a hammer.
[/QUOTE]

I don’t know about “smash” but there is good information here. The reason the studs seize is twofold. There is the build up rust mentioned above, but from all the extreme heat over time, the stud will actually “weld“ itself into the hole. Not like you would weld a piece of angle, just a tiny little bit, but considering the size of the stud, it’s enough to seize it. Think of gaulding a shaft or such if it gets too hot without lubrication, same concept. One thing you can do to try and break it free whether it is rust or true seizure, is to sharply rap the end of the stud with a hammer, as if you were driving a nail, but you don’t want to hit it that hard, you just want to shake it loose. The wraps should be firm, but not enough to damage the end of the stud or mushroom it. You want to use a steel hammer, not brass, and you want to rap it a bunch of times with sharp firm taps, rather than one hard smash.

Back to the nuts, the third of my two comments is to use the “too small socket“ method like you would use to remove a rounded off lug nut or a locking lug nut. If the nut is all rusted out, drive the next size smaller socket over it, and you’ll get some bite and leverage, BUTTT: be careful not to spin the stud off, and if you try this and it doesn’t work, it can be hard to get the socket back off. The reason I like this instead of going straight to the vice grips is because it doesn’t round off everything and shave it thinner if it doesn’t work the first time.

And the fourth of my two comments, is to use double nuts tightened down on the stud before you go to the vice grips. Put two nuts on, don’t run them all the way down, and then tighten them against each other. Then use a wrench on the inner nut and try to twist the stud out. The reason you use the inner nut is it will tighten as you pull, where the outer one may just break free on the thread.

Having said all this, if they’ve only been in there four years, I doubt you’re going to have that much trouble, but I wanted to share the whole thing for others who might not have gone through it.

Finally, if none of that works, as it says in the Navy manual: “get a bigger hammer,” and bash the crap out of the nuts, the studs, the manifold and anything else you feel like (but not the wife) until you feel better!

My 2 cents, hope it helps...

 

[Ramcharger90]

Atleast it's not a 5.4 Triton