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I understand what you are saying. It appears on mine they drilled a hole in the manifold and threaded in some type of aftermarket choke tube. i'll take a pic and show you.

as for the cover plate...why would you want small hole in it....seems like that would create an exhaust leak.

my plan was to keep using the aftermarket choke tube and put a freeze plug in the choke stove and a couple of bolt hole plugs (yeah sorry don't know the name), but you can get them at Lowes and they have allen heads on them.

Henry, could be wrong, but there should be not a direct path from the exhaust gasses in the manifold to the choke stove area. The area is heated by the gasses flowing through the manifold. The small hole in the stove cover is needed for the light vacuum draw from the carburetor's choke through the choke stove so warmed air can be drawn into the choke housing. Without a small hole in the stove cover a vacuum will be created and there will be no warmed air flow.

The cleaned and painted front end look great.

Now would be a good time to refill the front shocks.

(o[]o)

thanks for the information.

shocks were on the agenda

Choke stove is open to exhaust, just checked. So original question stands... wouldn't that hole create and exhaust leak?

If your tube goes directly into the manifold, yes there would be something which could be considered an exhaust leak -- and if the engine runs rich or burns oil, soot will be drawn in and could cover the components inside the choke mechanism and might cause issues.

The manifold heaters after your type are shown in the illustration. Those had a stainless or maybe just a good quality steel tube which was inserted or driven in a cast pair of holes in the manifold. It was a straight thru tube with a restriction on the bottom end to limit air flow. Exhaust warmed the tube which in turn warmed the outside air as it was drawn thru to the choke mechanism. The tube going to the choke just slid into the top of the steel heater tube. That second tube was not press fit but was similar to the same setup turned on it s side as used on your 55.

You could do similar by using a cup type freeze plug on that large hole. Make a chamber out of it and then do the screw on cover plate as Fred mentioned. Drill a small hole in the plate for an air inlet and attach the fitting in another spot to connect to the car.b. The exhaust would heat the cup which would heat the air inside the chamber and work the same as the straight tube on later manifolds.

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This is how my choke tube looks and the hole it mounts in. I will reuse this and plug the choke stove.

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Henry, like I first posted "...could be wrong, but..." Looking at the 1935-1941 Parts List there is an illustration of the carburetor and its automatic choke mechanism.

It looks to me as originally built there is no hot air tube from the choke stove to the carb. There is a thermostatic spring and mechanism that fits into the manifold opening which operates the choke with levers and links.

So, Howard's recommendation is a good work around for this problem. Or, you could simply clamp a piece of tubing from the carb's choke housing on to the exhaust manifold. Simple and direct. This has been done before by others with good success. Of course you still would need to install a plug in the choke stove opening.

(o[]o)

I am kind of curious about that fitting on the end of your tube which fits in the manifold. Is it just an open chamber so exhaust gases can pass thru to the choke or is it a closed cylinder with maybe a tiny hole in the side or top of the nut that would allow air to be drawn thru and heated.

If it is an open chamber I would really wonder about possible fouling or damage to passages or pieces in the choke mechanism if they were coated with exhaust byproducts when the vacuum draws them in.

JW. I think you are looking at the Stromberg carb. mine is the carter. no mechanical linkage for the carter from the manifold.

the carter hooks up just like the 55/56 with a thermostatic tube running from the manifold to heat the choke on the side of the carb.

HH. The unit that screws into the manifold is solid. it reminds me of a mechanical water temp gauge tip. the tube is stuck on the top of this thing that goes in the manifold. it does not appear that there are any holes that open the tube to the exhaust gases, just the heat itself. it pretty much reminds me of the 55/56 setup, except it unscrews.

to me it looks like someone added it and probably drilled the hole in the manifold to fit it. and then plugged the choke stove that is for the Stromberg carb with a deep freeze plug.

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If it is solid I am really curious from where it gets air or how vacuum is able to pull heated air so enough passes over the bimetallic coil in the plastic housing to open the choke.