auto chokes
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Senior User
Joined: Dec 2001
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auto chokes
guys
can someone tell me exactly how an auto choke works? im particularly curious how that dial on the side (that says rich/lean) works. when i loosened the screws and turned it, i heard what sounded like a vacuum hiss? i was under the impression that auto chokes were electric. If this is the case, why is there ported vacuum running there (i think)
can someone tell me exactly how an auto choke works? im particularly curious how that dial on the side (that says rich/lean) works. when i loosened the screws and turned it, i heard what sounded like a vacuum hiss? i was under the impression that auto chokes were electric. If this is the case, why is there ported vacuum running there (i think)
Freshman User
Joined: Feb 2002
Posts: 49
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From: San Antonio usa
auto chokes
im not really what you would call well versed in the choke subject...but i have taken my carbureator apart about 1000 times this month... there is a hose that connects to the bottom of the choke... i beleive it has something to do with the choke reacting to some sort of thermal input.. i think they call it a chimney or something.. that may be the suction noise you hear.
Post Fiend
Joined: Apr 2002
Posts: 7,157
Likes: 1
From: Central Kali
auto chokes
If you take the three screws off that hold the choke assembly on, you will find a hole near one of them that is a vacuum port. Two tubes go down to the exhaust manifold. There is a sealed passage in the manifold that heats the air going through it. The tubes never seem to stay attached to the manifold.
Vacuum draws air from the inlet tube back to the choke housing where it heats up the bi-metalic strip which opens the choke as the engine warms up. Works ok except for the tubes always coming off the manifold.
Vacuum draws air from the inlet tube back to the choke housing where it heats up the bi-metalic strip which opens the choke as the engine warms up. Works ok except for the tubes always coming off the manifold.
Posting Legend
Joined: Sep 2001
Posts: 30,255
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auto chokes
The tubes rust out where they crimp into the plate because of the deformation, heat, and vibration. If you can't get a replacement use a 3/16-1/4" thick piece of steel cut to shape and drilled for mounting holes. Tap the plate for two 1/8" npt pipe fittings with compression nut fittings for 1/4" tubing. Drill thru the fittings with a 1/4" drill bit. Install the fittings in the plate. Make a loop around a broom handle very carefully with 1/4" copper or steel tubing (copper bends easier). Leave legs long enough to reach the choke on the loop and push it thru the fittings. Install the compression nuts and secure the loop to the plate. Install the plate assy with a gasket, bend the tubes to meet the choke and air cleaner. Fasten the tube to the choke like the original.
A nice fun fabrication job! But it is worth it to keep that hot air choke working.
[link:www.ford-trucks.com/guidelines.html|FTE Moderator]
over!
A nice fun fabrication job! But it is worth it to keep that hot air choke working.
[link:www.ford-trucks.com/guidelines.html|FTE Moderator]
over!
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