[dmsfrr]

Originally Posted by Daves55Sedan

The tube running inside the manifold MUST be continuous and without flaws (corrosion, holes, etc). If the tube is compromised, the surrounding vacuum will suck vacuum through any hole in the tube and negate the purpose (which is to transfer heat from the intake heat-riser passage up to the auto-choke spring housing). ...

There is no vacuum inside the large center crossover of the intake manifold, it's for exhaust, to heat the carburetor and a thin tube for the hot air choke setup of a T-Bird carburetor. See photos 2 and 3 in comment # 2 above.

zuburg;
Questions:
1. When would you use the mushroom plug mentioned above?
> > The mushroom cap can be used in place of the air inlet tube on the drivers side. On a '56 that tube draws air in from inside the air cleaner / carburetor. The mushroom cap is NOT a plug, it is open on the flat side and is an air inlet fitting.
photo # 1

2. What would happen if you had the inlet tube connected but the outlet side plugged? Would it still run? Would the choke effectively not work? I live in NC, pretty moderate temps. The car started set up this way, even with all it’s other issues.
> > The choke would not have heated air to operate it. Carburetor vacuum draws clean air into the small crossover tube from the drivers side, it is heated inside the exhaust crossover of the intake manifold, then is drawn up thru the choke housing to heat the coiled spring and continues into the carburetor.

3. What would happen if I hooked up both the inlet and outlet tubes as normal, knowing the crossover tube does not hold pressure? Would I get some heat to help the choke?
> > Exhaust debris and corrosive fumes would clog the choke mechanism and also vent thru the tube on the drivers side into the carburetor.
The center passage of the intake manifold is an exhaust crossover. photo # 2
It heats the carburetor when the engine is cold. Exhaust is forced thru it by a heat riser valve on the back end of a T-Bird passenger side exhaust manifold. photo # 3
The heat riser valve is usually removed from cars that aren't 'daily drivers' during winter weather.

4. I have one new line with fittings that I have yet to install and am not sure what it is (last picture). The only thing I can think of is the fuel line going to the fuel pump. I currently have a rubber fuel hose connecting the metal line from the tank with a short line from the fuel pump.

5. I searched for some info on an electric choke in case I needed to do that to solve my problem with the heat tube but didn’t find any specifics other than you might have to modify one to work in the opposite direction. Any pointers to specific posts? I FOUND A YOUTUBE VIDEO ON HOW TO INSTALL ELECTRIC CHOKE TO HOLLY 4000 (LOOKS EASY AND STRAIGHTFORWARD) If I go this route, do I plug both holes for the long heat tube?
> > Yes, both small holes for the leaky thin tube will need to be plugged at their outside ends or exhaust will be blowing out of them.
An electric or manual choke may be the easiest solution at this point.
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