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Well, I was cleaning up the manifolds today and I broke the tube that goes out from the top of the exhaust manifold and goes through to the bottom. Connects to the carb.

I seem to be having trouble finding info on what this tube is, what it does and what it's supposed to look like. Best I can find is on page 15 of the fuel & exhaust service manual.

What is it what does it do, where's it supposed to go to/from and how do I replace it?

That's a heat tube that supplies hot air to the choke. You need it. Define what you mean by "broke it", did you just break the top off where it sticks out a little, or is the whole thing destroyed?

And there's actually two pieces of this tube, per say. There's a piece that's supposed to be permanently in the manifold, and the other piece that actually goes from that tube to the carb. If it's the latter, you can make a new one using a piece of brake line and a compression fitting. If it's the former, that's a little more difficult but can be done as well.

It's the choke heat tube, goes "through" the exh manifold, then another tube connects by just pushing into the manifold and goes to the choke mechanism on the carb. Vacuum from the carb pulls heated air up the tube and warms the thermostatoic spring in the housing, gradually opening the choke as the engine warms up.

Fred Kanter
Kanter Auto Products
Boonton NJ

it must have been very brittle. I just barely grazed it and it broke off flush with the top of the manifold.

Don't worry about it then, as long as you can put the tube from the carb in it and it stays there then it's not really an issue.

Dave,

Common for a 50+ year old steel tube connected to a 500+? degree exhaust manifold to get brittle.

So just grab the broken piece with some needle nose and pull it out?

If it's the piece that's not part of the manifold, yes. If it is, then don't try to remove it, just make it big enough for a new tube to fit in it.

Is this stuff documented anywhere?
I had a devil of a time finding anything on it.

I wouldn't say "documented" per say, but more like "common knowledge" to those who've worked on cars like these for years.

You can learn a lot from older people if they're worth learning from.