What is this??
Cargo Master
Joined: Dec 2004
Posts: 3,362
Likes: 22
From: Florence, SC
That is a thermostatic hot water choke. The insulation is to help retain heat. Other models used a thermostatic hot air choke.
The brass fitting originally connected to the choke housing on the stock Motorcraft 2150 carburetor. The tubing routes into a water jacket that contains engine coolant. The hot water choke is designed to calibrate the opening of the choke plate by the temperature of the coolant. As the engine warms up, the coolant gets hotter and that heat gradually unwinds the spring inside the choke cap until the choke is fully open.
Aftermarket carburetors typically do not use thermostatic chokes. They usually have fully electric choke caps. That explains why yours is disconnected.
The brass fitting originally connected to the choke housing on the stock Motorcraft 2150 carburetor. The tubing routes into a water jacket that contains engine coolant. The hot water choke is designed to calibrate the opening of the choke plate by the temperature of the coolant. As the engine warms up, the coolant gets hotter and that heat gradually unwinds the spring inside the choke cap until the choke is fully open.
Aftermarket carburetors typically do not use thermostatic chokes. They usually have fully electric choke caps. That explains why yours is disconnected.
Lead Driver
Joined: Apr 2007
Posts: 5,958
Likes: 105
From: Houston
their use of a choke cable inside is just the simple over used excuse of not knowing how to hook up an electric choke properly. Or maybe they feel electric chokes can open too fast and rather control it manually.
pedant
Joined: Jan 2008
Posts: 23,576
Likes: 40
From: EXTREME southwest CT
The open filter element isn't helping cold starts in any way.
It's no wonder they could not get an electric choke to function properly and "fixed" it by going to a cable.
BTW, that's a hot air choke.
You can see it coming from the lozenge shaped choke stove in the exhaust crossover of the intake manifold
It's no wonder they could not get an electric choke to function properly and "fixed" it by going to a cable.
BTW, that's a hot air choke.
You can see it coming from the lozenge shaped choke stove in the exhaust crossover of the intake manifold
Moderator
Joined: Nov 2007
Posts: 22,415
Likes: 92
From: Denver Metro Area, CO
You will like the factory-type of air cleaner setup if you live in a cold climate (and especially if you need to park outdoors).
Watch this video on adjusting electric chokes, it will at least give you an idea of what they are and how they work:
Watch this video on adjusting electric chokes, it will at least give you an idea of what they are and how they work:
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FTE Legend
Joined: Nov 2015
Posts: 30,955
Likes: 4,126
From: Angier, NC
That is a thermostatic hot water choke. The insulation is to help retain heat. Other models used a thermostatic hot air choke.
The brass fitting originally connected to the choke housing on the stock Motorcraft 2150 carburetor. The tubing routes into a water jacket that contains engine coolant. The hot water choke is designed to calibrate the opening of the choke plate by the temperature of the coolant. As the engine warms up, the coolant gets hotter and that heat gradually unwinds the spring inside the choke cap until the choke is fully open.
Aftermarket carburetors typically do not use thermostatic chokes. They usually have fully electric choke caps. That explains why yours is disconnected.
The brass fitting originally connected to the choke housing on the stock Motorcraft 2150 carburetor. The tubing routes into a water jacket that contains engine coolant. The hot water choke is designed to calibrate the opening of the choke plate by the temperature of the coolant. As the engine warms up, the coolant gets hotter and that heat gradually unwinds the spring inside the choke cap until the choke is fully open.
Aftermarket carburetors typically do not use thermostatic chokes. They usually have fully electric choke caps. That explains why yours is disconnected.
There is a loop of metal tubing that goes into the intakes exhaust cross over port to heat the loop.
The other end of the heating tube goes up to the stock air filter assy. To pull in clean air.
Dave - - - -
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Cargo Master
Joined: Dec 2004
Posts: 3,362
Likes: 22
From: Florence, SC
Originally Posted by ArdWrknTrk
BTW, that's a hot air choke.
You can see it coming from the lozenge shaped choke stove in the exhaust crossover of the intake manifold
You can see it coming from the lozenge shaped choke stove in the exhaust crossover of the intake manifold
Originally Posted by FuzzFace2
that is not hot water but hot air.
There is a loop of metal tubing that goes into the intakes exhaust cross over port to heat the loop.
The other end of the heating tube goes up to the stock air filter assy. To pull in clean air.
Dave - - - -
There is a loop of metal tubing that goes into the intakes exhaust cross over port to heat the loop.
The other end of the heating tube goes up to the stock air filter assy. To pull in clean air.
Dave - - - -
I thought if the hot air tube bolted to the intake manifold, it was a hot water choke? Didn't some engines/models use engine coolant to heat up the hot air tube?
pedant
Joined: Jan 2008
Posts: 23,576
Likes: 40
From: EXTREME southwest CT
Im not certain about 335 series engines.
Gary Lewis or Chris could probably elaborate.
351 W's definitely had a choke stove in the exhaust crossover.
There wouldn't be any need for high temp fiberglass insulation if it were heated by coolant that (hopefully) never gets above 225*
A lot of engines used exhaust gas to heat the intake plenum floor.
This discourages puddling and helps vaporize fuel in cold weather.
Gary Lewis or Chris could probably elaborate.
351 W's definitely had a choke stove in the exhaust crossover.
There wouldn't be any need for high temp fiberglass insulation if it were heated by coolant that (hopefully) never gets above 225*
A lot of engines used exhaust gas to heat the intake plenum floor.
This discourages puddling and helps vaporize fuel in cold weather.
Moderator
Joined: Nov 2007
Posts: 22,415
Likes: 92
From: Denver Metro Area, CO
IIRC those coiled-up things went into the exhaust stream used by the EGR stuff... had to have been that way on the 335 series as theose didn't have any sort of coolant crossover passages in the intake manifold, water flowed through the block & heads only.
FTE Legend
Joined: Nov 2015
Posts: 30,955
Likes: 4,126
From: Angier, NC
I don't know what model that is on but I am 99.99% sure it is air that gets heater from the exh cross over that also heats the intake floor as was said.
AMC motors used that same hot air setup for the choke and also had a bracket held on with the 3 screws for the choke cover that held a heater hose next to the cover.
This would help heat the choke kind of like the low volt & hot air system Ford uses that I have seen posted about.
Hot air tube to choke on my AMC 360 – No it is not a Ford360!
Intake showing the choke heater unit installed
Don’t have any pictures of it all pretty and hooked up tocarb as I am still working on this car but it does work as the motor does run.
Dave ----
AMC motors used that same hot air setup for the choke and also had a bracket held on with the 3 screws for the choke cover that held a heater hose next to the cover.
This would help heat the choke kind of like the low volt & hot air system Ford uses that I have seen posted about.
Hot air tube to choke on my AMC 360 – No it is not a Ford360!
Intake showing the choke heater unit installed
Don’t have any pictures of it all pretty and hooked up tocarb as I am still working on this car but it does work as the motor does run.
Dave ----
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