Hole in the exhaust manifold?

Heres a question for ya. My '66 has the original 340 and I was looking around in the engine compartment the other day and found a hole in the exhaust manifold on the passenger side. The hole is perfectly round and right smack in the middle of the thing on the top. It is about the width of a pencil. Is this hole functional? Is it supposed to have something coming out of it or has the rust just chewed a perfect circle through my manifold? There are several loose lines floating around in my engine compartment being that the guy who previously owned this car just disconnected stuff that he didn't recognize. Thanks for your help.

 

I think the hole your talking about is used for the choke on the original carb. Just a guess though.
Philip

 

I spoke incorrectly. It is on the header. Here is a picture of it.

 

SOmeone may of had an exhaust temp sensor in it? or maybe done to pass emmsion test. with that wire next to it, it looks like it could of helped hold somethig in place there.

weld it, jb weld it. tap the hole and put a shallow plug in it.

 

That is correct. There should be a steel line that is run up to the choke. Just about every one I have seen rusts away to nothing. I usually use copper tubing to replace it since it won't rust. It just pushes in the hole until snug........ kinda like a dipstick tube does.


Mike

 

I think the hole your talking about is used for the choke on the original carb. Just a guess though.
Philip

Philip you are correct on your guess.
A small metal pipe would go from that hole to the choke for the heat riser tube.
This pipe kit is available at most auto parts stores.

 

Mike beat me by a minuteou:

 

Nah, all of you are wrong. That opening is known as the "oil consumption" hole. When you see oil smoke coming out of the hole like an old steam locomotive, time for engine work! :Brow:
Great idea since no one can see the oil smoke coming out of their tailpipe! Those Buick engineers think of everything!ou: :laugh: :laugh: :TU:

 

thanks for your help, guys. So, what exactly should I ask for when I go into the store? Also, if I just get so frustrated that I decide to plug it, will I be up a creek?

 

If you don't need a choke set-up, just plug it.

If you need choke, go to Home Depot and get a pipe to tube compression fitting. Then run a tube from the fitting to the carb connection. The opening appears to be a 1/8" NPT, pipe thread.

 

Thanks so much. You guys rock.