My car has 117,000 miles and I don't think it has ever had the exhaust manifolds removed. I am going to be removing them and replacing them with headers. I have read about busted bolts, etc and am hoping to gather some lessons learned and best practices so that I might have a smooth removal.

 

The bolts most likely to break will be to the y pipe and you won't be reusing them so you won't have to worry about them. Will be a fun little project hop you put up some pics of your y pipe. Make sure you have plug wires with 90 degree boots for the headers.

 

Been there done that, I even soaked mine with penetration oil for two days before starting the project and wound up with one broken off in the driver's side head; Hope I'm wrong, but I see a head removal and a helicoil installation in your near future.

 

Thanks guys. I'll use penetrant, an impact wrench, and go to church. I'll post up some pics as I get it done.

Here's the headers:



They were a "rescue" from Lurbie (Jeremy), who was kind enough to work with me on packing and shipping.

 

When I broke a bolt off in the head, I just hooked up the welder, took a nut and welded the nut to the broken bolt and removed it.

 

Don't use an impact on the manifold to head bolts. Soak the snot out of em and use a good 6 point socket and ratchet. Impact will most definitely snap them. Don't really think you could get an impact in there anyways. Just take your time. Whatever you do, don't use a 12 point socket/wrench.

 

if you've never removed stock manifold bolts, look very carefully at them before you put a socket on 'em. a few of them will have a thin steel piece that can be barely visible. after the factory installs the bolts, they bend over usually 2 tangs on the shoulder of the hex. this is to prevent the bolt from loosening up over time. you will need to take a flat screwdriver or such tool to bend the tangs out before trying to remove the bolt.

i agree about penetrating oil. sometimes i lightly try to tighten the bolt before loosening. this helps work the bolt loose. in fact it's great practice when removing any steel fastener from aluminum. almost a guarantee to never snap a bolt in aluminum again.

best of luck on the manifold removal. it wont be that bad.

these are the locking tabs you must bend out/away from the hex first;
http://www.classicchevy.com/chevy-ex...lock-1957.html

 

I tried that too, the nut would simply break off another section of the exposed stud; it's pretty clear that GM fudged on the hardness of those bolts in the 80's.

 

The most difficult part will be the nuts that fasten the brackets and heat shields.
The bolt will come loose and start to twist the sheet metal parts before the nut comes loose.

I heat the nut first. it makes it break loose before the bolt turns.

 

I always soak them in penetrant a few days ahead of time. If I know I'm doing it I might even do it weeks ahead of time and soak them every few days and drive it to get it to soak in.

That said, i've done a bunch of them, 1/3 that didn't get any penetrant ahead of starting that came out fine. AAMOF, most have a few bolts loose enough that you can usually get them out with your hands.

As has already been said, typically the hardest part is the studs that have nuts on them holding a bracket or other sheetmetal, and about half the time I've broken one or more studs attaching the y-pipe which usually doesn't matter if you're not re-installing them (I typically soak them down, then get under the car with an impact and extension and assume I'm going to break them off but sometimes the nuts come off fine)