Exhaust Manifold Stuck

[swettysblazer]

I am working on the motor I bought for my 78 K5. Just a 350, stock for the most part. I have run into a little issue however.

The right side of the motor is a little bit different than the left. Different size exhaust manifold bolts, two broken spark plugs, no biggie. The issue is that I cannot get the exhaust manifold off. I had to cut the heads off of the bolts, and they still will not come off. I have been beating, prying, heating, soaking, and doing whatever I can think of to try and get this thing off. My next step is drilling the bolts out, Which I would rather not do. Any tips or tricks? I don't need to save the manifold.

 

[sweetk30]

air hammer with button head bit . don't go full on the trigger but little bit and work your way up .

button head the area were the buldge is for the bolt .

works wounders . you might even see the rust come flying out of the holes.

 

[swettysblazer]

What is this button head bit you speak of?

 

[brans87]

thinking he is referring to the one on far left

 

[sweetk30]

ya daaa

not a chisel bit / not a cutter bit / a button head .

i have both a flat and a concave one . the concave works great for staying on a bolt or corner or shape with out walking off the side in .00012 seconds of the trigger getting pulled.

if your good with a air hammer . you can do it with a punch bit . just dont get to crazy and break the piece your hammering . . . unless you dont care about it .

 

[ChrisPerry]

Which bolts? All 6 or just a few?

 

[swettysblazer]

All 6 are locked tight. I will see if one of the guys at work has this button head.

 

[diesel4me]

I've removed a few dozen exhaust manifolds at the junkyard that had bolts too rotted to be removed with a wrench,we had to torch off the bolt heads,and used a 3 foot pry bar to pry the manifold off over the remaining "studs" of the cut bolts--often they were very stubborn and felt like they were welded right to the cylinder heads,but persistence usually prevailed--if you pry on the manifold between the head with the bar,and pull on the manifold's pipe outlet in and out,eventually they'll loosen up around the bolt remains and come off..

We started some of the engines up if they ran,and let the manifolds heat up too,that helped break the rust free as they expanded..

The air hammer trick probably works well too,but we didn't have the luxury of air tools or a portable compressor at the junkyard..

If your not concerned about re-using the manifold,I have had to cut several off with a sawsall,using a Lenox metal blade--start at the front most bolt and cut right thru the manifold and bolts--the manifolds cut a lot easier and faster than you'd expect,the bolts can be tough sometimes due to being hardened by the heating & cooling cycles..
I've had to smash the manifold remains with a hammer to get them loose where the bolts pass thru them..