Advice for pulling exhaust bolts????

Need to change the exhaust manifolds on my '56 Pontiac 316.......Pretty sure the originals have never been off, but a chunk broke off one of them (notorious for breaking at the elbow on factory duals).
Anyhow, I don't want to disable the car for the rest of the summer......any tips for pulling the manifolds? My biggest concern is breaking bolts/studs off in the block.....
Thanks for any advice!
Johnny

 

Soak em daily for 2 weeks with Kroil and/or acetone/ATF mix...

 

Ah!!!! That reminds me!! Does any grade of ATF work in that mix? I think
i have four different kinds laying around here!

 

They come loose best when hot.

 

gibbs brand, gibbs brand, gibbs brand.

sure, a little expensive per unit, but there is NOTHING better IMHO.

give 'em a good soak once per day for three days. follow application with a little vibration.... tap the heads of the bolts with a small ball peen hammer or something similar. do the same prior to attempting to remove.

good luck

 

liquid drain-o, put it on the bolts and let it seap in to the threads, for some reason the chemicals in it break down the rust, ive used it before to get the bolts at the bottom of the manifolds off

 

soak em...soak em...soak em

 

The old timers new best. Heat them and soak parafin wax into the threads. Works better than anything

 

Soak in penitrating oil for a couple days. Warm them and carefuly take em off. Even if the bolt head pops off there should be enough shaft to use vise grips to get off once the rest of the bolts and/or heads are off and the manifold slips off.

Reinstall with thread anti seize and new bolts.

 

heat works when everything else fails

 

I dont chase threads on exhaust manifold bolts as it tends to make them a bit loose.

 

Once they're good and soaked and you're ready to try and remove them, tighten them a little first, then try to loosen.....good luck, but with bolts as old as these plus being in an exhaust application - I'd plan on most of them breaking. And I'd definitely plan on replacing all of them. I think the only antisieze that will work in heat applications is the copper stuff......

 

Id heat them up { not red hot } then rap the head once or twice with a hammer should knock the threads loose.

 

#$#$ Patience !!!! >>>>.

 

This is the way to do it!

 

Soake them for a day or so than Take it for a ride to heat them up and when you pull into the garadge pop the hood and start wrenching. and like another poster said give it a 1/8 turn tighter and than loosen it. some times loosining it a little than go back and forth to helpclean the threads. good luck

 

Then use a spray bottle with diesel & WD40, mix 50/50

 

I've had success with gettin 'em hot, and sprayin WD40 on 'em several days in a row, rappin 'em with a ballpeen as well. The light oil seems to wick into the threads pretty well and works best when they're hot. Good luck.

 

If they're gonna break, they're gonna break. Because the manifold is in the way, you can only soak the head, and not the threads.

 

Save yourself the hassle. Buy a handfull of drill bits, a case of beer, hit em' with the air ratchet until they break and enjoy the rest of your weekend haha.

j/k...soak em', heat em' and cross your fingers!

 

Personally, I just twist them off. They are rusted into the manifold, not the head. Nearly always break just below the bolt head. Now with a generous dose of penetrant, not wd40, and a couple bars, work the manifold off. I've never had a manifold bolt that didn't screw right out of the block once the manifold was off. Iff the heads round off without breaking, just blow them off with a torch. Won't hurt the manifold. Just use common sense about doing other damage with the torch, like burning off the plug wire and such.

 

I removed the manifolds from an old flathead that had been outside forever. Of course they all broke, and I thought crap!!, but once the heads were out of the way, the manifolds slipped off, and the remainders of the the bolts came out easily with a vise grip, after soaking of course.

 

That right there is the gospel!

Break em off if that's what they want, slip the manifold off and then pull the "Studs" that are left over.

 

Problem is, removing rusty exhaust manifold to head bolts on a Pontiac V8 can be a real pain in the ass, too. The ports angle down towards the ground and, chances are, the heads on those bolts aren't even hexagonal anymore after 55 years. When I had to replace the exhaust manifold gaskets on my '68 LeMans, I said, "Well, only ten bolts hold the heads on, and it could probably use new head gaskets anyway....." and ripped the heads off and worked on the bolts on the bench. Believe it or not, much easier on the brain cells and knuckles!

 

Most of these are good ideas, IF AND WHEN you do twist one off, do not drill until all else fails! Weld a oversized nut to the stud after manifolds off. Have socket ready because as soon as the red goes away thats when it will come out easiest. Sucky job, GOOD LUCK!!!

 

We used to heat the bolt up red hot then spray water to cool it fast, they would come right out then. Don't heat the manifold.

 

A mechanic that used to work at the dealership where I work used to swear by your method, and had good luck with it.

 

on reinstall , use brass nutz ..................... steve

 

if the bolt heads are brunt undersize sears has a tool set that works on them. they are called easy off. they will even work on the stud that is left if the head breaks off. i just used one on my chevy truck to get some out. now after you get them out through them all away and get new stainless steel bolts and antisize and you will never have this problem again.

 

Now I'm ready to pull the heads on my flathead in the morning! thanks for all the good advise guys and thank you search function