1972 350 exhaust manifolds

[bonesbmx]

hey guys glad to be back on i need to remove my exhaust manifolds. i can tell that these have never been off before. ive been putting on penetrating oil for about a week. my socket wont fit over the heads they are rusty and look odd shaped from layers of rust a friend told me that factory bolts had a lock so to speak to keep from vibrating out so the bolts will look to be deformed and that a flat head to push those down will let the socket fit. is this true? also how many bolts per manifold? what kind of chemical can i use to bring the rusty manifolds back down to metal?

any help would be great

thanks

[millwrightrice]

There are 6 bolts.
If the lock tabs are still there they are real noticable
If the head rounds off Craftsman makes a set of really cool bolt or nut removers.A friend bought me some and I used them on my exhaust.The middle bolt is the toughest.
Have them sand blasted.Chemicals won't do any better.

[Oldsguy]

bones,
Look real hard for those lock tabs, I have seen them so rusted that it appears they are part of the bolt head. If, they aren't there, or after you remove them, you still can't get the bolts out you might try a vice-grip wrench, about the medium 6" size should work. You won't want to re-use the bolts anyway after you get them off so don't worry about damaging the heads. Your best bet would be to take them to a media-sand blasting outfit to clean them off if that is what you are after. The will rust again though so why worry, just use a good steel-wire wheel to clean them up enough for correct re-assembly. Then go back and re-tighten them next week, and the next.

[bonesbmx]

thanks guys
oldsguy hit it exactly it looks like something is on the bolt head. im going to give it a shot and ill definately get a set of those bolt removers. where can i buy a set of new bolts? should i use some kind of thread locker?

thanks

[joe_padavano]

Originally Posted by millwrightrice

There are 6 bolts.

Actually, there are five. One at each end, one above the center two exhaust ports and one on each side of the center two ports. The factory used C-shaped sheet metal retainers that went under the front two and back two bolts with the lock tabs mentioned previously. You need to pry these tabs back (a flat blade screwdriver is the tool of choice, with a small hammer for motive force). Since the threads are in blind holes that angle upward, penetrating oil will have virtually no effect. He best technique is to pry back the tabs then if possible run the motor until it heats up. This makes working around the motor tricky but helps loosen the bolts. If the heads are rusted to where a socket it loose, DO NOT round the bolt heads. Instead, try the next smallest METRIC socket. You may need to pound the socket onto the bolt head, but the smaller metric size often makes up for the metal lost to rust. Also, be sure to only use 6-point sockets.

[Oldsguy]

Good point Joe, I knew metrics where good for something.

[millwrightrice]

OOOpsies there are 5 must have had a brain fart since I finished my engine last week.The bolts on mine were through bolts except the 1 middle one so solvent would help.Remember to chase the threads with a tap before re-installing.Go to the local hdwe store and get some grd 8 bolts that will be fine.Try to use a shorter bolt on the middle one the original one is ridiculously long.Year One makes the lock tabs to put back on that's what I used.That way I could use anti-seize instead of loc-tite.So if I decide to put headers on removing is not much of an issue.Remember use the best of modern technology when available slamming metric sockets with the chance of shattering is when your desperate and in a bind.

[bonesbmx]

thanks guys all the help is awesome

[joe_padavano]

Originally Posted by millwrightrice

The bolts on mine were through bolts except the 1 middle one so solvent would help.

You're right. MY turn for a brain fart...