nada

I'm getting great feedback on doing this manifold change and upgrade. However, instances of bolts breaking off in the heads and cracking of the manifolds kind of gives me the heebeegeebees! Is this something that occurs frequently? Can soaking the the bolts with WD40 or Breakfree make a big difference? I'm going to do the job. I just want to do all I can to make the job go well. Thanks for all the good poop and guidance!

Rick in Tennessee

71vettman

Yes..........they break often :smash:
Butt soaking them with wd40 and or a good penetrating oil is definitely a good idea. If they do break though its not the end of the world I work in a machine shop and we take broken studs out all the time. Its much easier once the head is out of the car. Good luck!
Kevin

Desertdawg

Try loosening them cold first. DON"T over torque them to get them loose, if they won't budge then Heat will definitely help.

If you break one off, take the rest of them out, and remove the manifold, it you will have more room to work on the broken ones then. I fought them on my 460, but none of them where impossible.

Alwyn678

I guess I got lucky I had no problems at all when I took them off to put on the headers. Came right off

Kenzy

Same here, but then again my valve covers leaked like a SOB!

ZD75blue

mine were so stuck... that i broke a manifold into a few pieces... dont ask :jester

desi

Do you use a torch for heat? Or just let the engine run for a while?? :confused:

Desertdawg

Try warning the motor up first. If that doesn't get it, then break out the torch. :mad

Crash Dummy

ZD75blue....

I've got the matching #'s engine sitting on the stand right now with one head still on because the manifold has two broken bolts that would not give no matter the lubricant. I fail to see how any loosening compounds/liquids can help at all when most of these manifolds have been on for so many years that nothing is going to leak down past the bolt on either end(bolt head or the head itself where the threads are). Little might I say.... that manifold is now in two pieces as I broke it attempting to work it off the head. One thing I have to say about Sears is that their specialty sockets to grab rounded bolts can break the head off of anything. I have two of them on this manifold to prove it.

Edzred72

Well Rick, I'm one of those sob stories. I also asked a ton of advise when attempting the removal of ex manifolds. I did everything possable, and a severly rusted bolt snapped off anyway. Even after removing the manifold, soaking for days, map gas torch, every type of wrench....the head had to come off. (reason for engine mods and new heads) It's a crap shoot! Another thing to be careful with. The exhaust manifold pipe mounting flange (bottom of manifold) is very brittle. One stud hole on that flange has very little material around it...breaks easy! Ask me how I know that ...after breaking both sides trying to remove the stud. :conehead If you can leave the ex-pipe studs alone...do so. After years of heat/rust removing them is very dangerous!!!
May the Vette gods be with you...good luck
Eddie :auto: :cheers: :smash: :smash: :auto: :smash: :smash:

IETEK

I know it is next to impossible to get any kind of impact or air ratchet on exhaust to loosen the bolts but, I would try where accessible. The vibration of the impact will usually break the bolts loose if you let it hammer for a while with out putting to much torque on the bolt.


Good Luck, IETEK :D

The Money Pit

I've been lucky with most of the Chevy's I've removed,and I think the design has a great deal to do with it. All the bolts tap into the head completely,as opposed to the F brand,where the end of the bolt protrudes from a flange cast into the head.Water gets to the threads and rust take care of the rest.Snapped many.You shouldn't have a problem at all with them.

Paul L

I have been reading with great interest as I may attempt an exhaust manifold removal this summer. I do wonder, however, if respondents are not mixing up manifold/head bolts with manifold/exhaust pipe studs (see pic). I fought the latter battle three summers ago for nine hours. Even with penetrating oil, acetylene and a stud extractor (second pic) I snapped four off. I eventually got them out by drilling. Had to re-tap one hole only.

But if I understand correctly the exhaust/head bolts can also snap. That is not pleasant to contemplate. And I cannot see any brand of penetrating oil getting into the threaded areas in the head by spraying the exhaust manifold/head junction. So I guess it is just a crapshoot: sometimes you win and sometimes you lose....






[Modified by paul79, 5:23 PM 3/8/2003]


[Modified by paul79, 5:25 PM 3/8/2003]

71vettman

Dont leave out the penetrating oil just because you dont see how it can get in there. It can and will eventually. Plan ahead and start spraying them a couple weeks ahead of time. dont just spray around the head bolt. make sure to spray where the manifold bolts meet the head too. Even if the penetrating oil only keeps one from snapping it was well worth it.

Sometimes you wont have any problem at all when romoving the manifolds you just have to be ready in the event that one or more snap off.
Kevin