Removing 6cyl Exhaust Manifold

[Airmapper]

Well I looked it over today, and it don't look good. I'm not well equipped for this kind of work. 45 years of rusted seizure, and I don't even need to round the bolt heads off since they are already round-ish.

So what do I need to do to get this off? I looked through my tools, and I don't think I have anything much that will help. A socket isn't going to work, and the bolt heads are too small to get anything else on easily. Even if I get a grip on what is left of the head I'm anticipating it will just twist off.

An idea I'm thinking on is cutting off the heads (If I can get to them) to remove the manifold first, then working with the shafts sticking out. I also know that heating the bolts with a torch might help, but at this point getting a grip on them is my main issue, heated or not.

Any insight on how to get this off would be greatly appreciated.

 

[75bronco08]

with no pix of the bolts i would think a good 6 point scocket would bit good enough to get them off.next thing i would try is welding nuts on to the bolt heads.im sure somebody will chime in with other suggestions

 

[Dr. Bronc]

I had the same issue--40 yrs of rust and heat and the bolt heads looked like little round blobs of metal.

To repair, I removed the motor from the Bronco and took a grinder to what was left of the bolt heads. Surprisingly, there is room to get the majority of the bolt heads cut enough to snap them off with a cold chisel. The exhaust manifold can then be removed. The only downside was I then had to cut the remaining portion of the bolt off, and then drill and tap new holes.

On the bright side, I was able to replace the blown out exhaust manifold gasket, which has significantly reduced my exhaust noise AND I now have grade 8 bolts in there with some anti-seize, which should help out if I have to remove it in the future.

I hope this helps. Good luck!

 

[shamu]

I had to pull off my cylinder head and had machine shop extract 2 bolts. I tried every thing listed above. The best part is that I have hardend seats and the 170 purrs like a kitten.

 

[TOFIC]

heres how I did a couple on a six I had

went down to the cheap store and bought a couple of cheapy socket sets.
found the right size for the rounded nuts and drilled a couple of holes in the side of the socket into the bolt head.
drilled theholes out to 1/8 inch and drifted in a couple of split pins
soaked the sn*t out of the bolts with PB blaster
put on the power bar and cranked them off. (not quite)
could not get one off so i welded the socket onto the bolt through enlarged holes in the side of the socket and off it came
stainless steel bolts with anti seize ended the problem ever popping up again.

 

[Jebus]

The best thing I have found on any exhaust manifold or oxygen sensor is to warm up the engine to operating temperature first. Being carefull not to burn oneself (GLOVES) the bolts will come out easier. Most of the time they will turn right out, where cold they are stuck and will break...
...JJG

 

[Airmapper]

Thanks for the ideas. Removing the motor would be a pain at this point, I'm hoping to do a full body off down the road, but right now I'm not set up for that.

Might be able to try the socket idea in conjunction with heat, PB beforehand. (Don't want to mix the two I don't believe... don't ask me how I figured that one out... ;D )

I'll try to get some pics this weekend of the bolt heads.