Carb choke question
#1
Carb choke question
I currently have a 2 barrel Motorcraft carb with no tag on my 68 390. The venturi numbers on the side are 1.21, which Pony Carbs tells me is the correct size for the engine (351 cfm). It has the mount for, but not the workings of, the choke pull off - which is no big deal since the carb itself has a manual choke.
I'm assuming that this carb was a replacement, and whoever put it on removed the automatic choke.
The truck stumbles off idle, it's worse when cold, somewhat better when warmed up. I'm assuming that the carb needs a rebuild, like most of the rest of the truck. I'm thinking of getting a (correct) Autolite carb, and rebuilding it myself.
Now, I can find Autolite carbs, but all of them have the auto choke. I'm wondering if it a simple deal to simply remove the auto choke and hook up the manual choke cable, and go from there.
Thanks!
I'm assuming that this carb was a replacement, and whoever put it on removed the automatic choke.
The truck stumbles off idle, it's worse when cold, somewhat better when warmed up. I'm assuming that the carb needs a rebuild, like most of the rest of the truck. I'm thinking of getting a (correct) Autolite carb, and rebuilding it myself.
Now, I can find Autolite carbs, but all of them have the auto choke. I'm wondering if it a simple deal to simply remove the auto choke and hook up the manual choke cable, and go from there.
Thanks!
#2
Join Date: Feb 2000
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Carb choke question
Check for exhaust heat in the intake under the carburetor. Cold engine, start the engine and lay the back of your finger on the intake below the carburetor. It should get uncomfortable real quick. If not check the heat riser in the left exhaust manifold. See if it works freely and closes when the engine is cold. Also look at the warm air supply hardware for the air cleaner. This stuff needs to be in place for cold weather operations. Ford used many different systems to provide quick warm up and warm air/fuel for winter operations. You also need a 190 thermostat.
William in Atlanta
William in Atlanta
#3
Carb choke question
>Check for exhaust heat in the intake under the carburetor.
>Cold engine, start the engine and lay the back of your
>finger on the intake below the carburetor. It should get
>uncomfortable real quick. If not check the heat riser in
>the left exhaust manifold. See if it works freely and
>closes when the engine is cold. Also look at the warm air
>supply hardware for the air cleaner. This stuff needs to be
>in place for cold weather operations. Ford used many
>different systems to provide quick warm up and warm air/fuel
>for winter operations. You also need a 190 thermostat.
>William in Atlanta
Thanks, William.
I just got a heat shield and snorkle that I bought off ebay - the paint is drying on them as we speak - to be installed when I take off the exhaust manifolds and have one welded and both of them trued up and matched to the gasket, as part of the exhaust system replacement.
I have a brand new 195 degree thermostat in (along with a new water neck). I will do the check for exhaust heat, but my real question centers around the carb.
Can I remove the automatic choke from an Autolite 2100, and just use my manual choke cable? Or do I need to find one that is manual choke already?
Thanks again!
>Cold engine, start the engine and lay the back of your
>finger on the intake below the carburetor. It should get
>uncomfortable real quick. If not check the heat riser in
>the left exhaust manifold. See if it works freely and
>closes when the engine is cold. Also look at the warm air
>supply hardware for the air cleaner. This stuff needs to be
>in place for cold weather operations. Ford used many
>different systems to provide quick warm up and warm air/fuel
>for winter operations. You also need a 190 thermostat.
>William in Atlanta
Thanks, William.
I just got a heat shield and snorkle that I bought off ebay - the paint is drying on them as we speak - to be installed when I take off the exhaust manifolds and have one welded and both of them trued up and matched to the gasket, as part of the exhaust system replacement.
I have a brand new 195 degree thermostat in (along with a new water neck). I will do the check for exhaust heat, but my real question centers around the carb.
Can I remove the automatic choke from an Autolite 2100, and just use my manual choke cable? Or do I need to find one that is manual choke already?
Thanks again!
#4
Join Date: Feb 2000
Location: Sun River St. George
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Carb choke question
Sometimes collecing the bits and pieces for these old Fords can be a real test! Personally I like automatic chokes and would put your 2100 back that way. Finding all the pieces will be a test. Since you know of "Pony Carburetors" I'd ask them if they sell a kit for this application or maybe a rebuilt carburetor. Honestly, If the budget can tolerate it I'd go for an Edelbrock Performer and 1406 600CFM. Check out JEGS for 300 CFM carburetors that fit this application and keep the 2V.
William in Atlanta
William in Atlanta
#5
Carb choke question
>Sometimes collecing the bits and pieces for these old Fords
>can be a real test! Personally I like automatic chokes and
>would put your 2100 back that way. Finding all the pieces
>will be a test. Since you know of "Pony Carburetors" I'd
>ask them if they sell a kit for this application or maybe a
>rebuilt carburetor. Honestly, If the budget can tolerate it
>I'd go for an Edelbrock Performer and 1406 600CFM. Check
>out JEGS for 300 CFM carburetors that fit this application
>and keep the 2V.
>William in Atlanta
Actually, I'm getting kind of addicted to ebay - I keep finding neat stuff...
I'm not sure that my truck came with an automatic choke, since it has the choke cable, bezel, ****, etc that all look like they are stock. It's a 68, btw. I will check Jegs out, but I think 300cfm might be a tad smallish, Pony says my current one is 351 cfm, and I saw another spot that listed it at 360 cfm?
>can be a real test! Personally I like automatic chokes and
>would put your 2100 back that way. Finding all the pieces
>will be a test. Since you know of "Pony Carburetors" I'd
>ask them if they sell a kit for this application or maybe a
>rebuilt carburetor. Honestly, If the budget can tolerate it
>I'd go for an Edelbrock Performer and 1406 600CFM. Check
>out JEGS for 300 CFM carburetors that fit this application
>and keep the 2V.
>William in Atlanta
Actually, I'm getting kind of addicted to ebay - I keep finding neat stuff...
I'm not sure that my truck came with an automatic choke, since it has the choke cable, bezel, ****, etc that all look like they are stock. It's a 68, btw. I will check Jegs out, but I think 300cfm might be a tad smallish, Pony says my current one is 351 cfm, and I saw another spot that listed it at 360 cfm?
#6
Carb choke question
I just talked with Pony again, according to them, all 68 390's came with a manual choke carb, which is a different casting than the automatic choke carbs. The stock exhaust manifolds do not have the provision for the hot air tube required by the auto choke, so if I wanted to go non-manual, I would have to go electric. If I stay with the 2V, I will stay with a manual choke.
Now to really confuse myself, I'm going to look at Jegs and 4V's
Now to really confuse myself, I'm going to look at Jegs and 4V's
#7
Join Date: Feb 2002
Location: Greater Austin, Texas
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Carb choke question
I am facing a very similar situation. I have a '71 360 that was originally equipped with manual choke. I want to convert to automatic. I have an electric choke coil, but the Ford coil incorporates a thermostat that turns it off if the ambient temp is less than 60 (so it will open slower using the conventional heat stove method). Well, my truck does not have a heat stove or a bypass valve. So I need to fashion a heat stove. I want something that looks pretty close to factory but I do not know what that looks like. Can anybody email me a picture of their factory heat stove setup for auto choke?
To answer the original question, you can buy a manual choke conversion kit and hook your factory choke cable to it. That's how this truck was setup before I started monkeying with it.
To answer the original question, you can buy a manual choke conversion kit and hook your factory choke cable to it. That's how this truck was setup before I started monkeying with it.
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#8
#9
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Carb choke question
>I'm sure I've seen a heat stove kit for the auto choke in
>the 'Help' line of accessories you can get at your local
>discount auto parts store.
Right, that is what I am planning to use, but wanted to make up something that looks like the original. As far as I can tell, the heat stove on Fords goes down the exhaust manifold (?) as opposed to being built into the intake manifold like on GMs. I have never seen one on a vehicle, or at least did not take note of it, so my information is very spotty. That's why I was hoping somebody could send me a picture.
>As for the manual choke, don't most conversion kits have the auto >choke housing adaptor?
Yes, that is how you do it. It has a piece that replaces the choke coil and then has an external hookup for the cable to actuate the choke linkage. It will also come with a cable, you just substitute the Ford factory cable in it's place.
>the 'Help' line of accessories you can get at your local
>discount auto parts store.
Right, that is what I am planning to use, but wanted to make up something that looks like the original. As far as I can tell, the heat stove on Fords goes down the exhaust manifold (?) as opposed to being built into the intake manifold like on GMs. I have never seen one on a vehicle, or at least did not take note of it, so my information is very spotty. That's why I was hoping somebody could send me a picture.
>As for the manual choke, don't most conversion kits have the auto >choke housing adaptor?
Yes, that is how you do it. It has a piece that replaces the choke coil and then has an external hookup for the cable to actuate the choke linkage. It will also come with a cable, you just substitute the Ford factory cable in it's place.
#10
Carb choke question
I made a hot air pickup for the air cleaner by welding up a short L shaped piece that is held by one bolt on the exhaust manifold. A short tube on the top uses aluminum flex to connect to the air cleaner. I use a Holley electric choke cap on my Ford 2bbl, works fine. Those factory hot air tubes for the choke are nothing but a headache. They rust off at the exhaust manifold or fall off so your choke is sucking cold air. :-(
#11
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Carb choke question
>I made a hot air pickup for the air cleaner by welding up a
>short L shaped piece that is held by one bolt on the exhaust
>manifold. A short tube on the top uses aluminum flex to
>connect to the air cleaner. I use a Holley electric choke
>cap on my Ford 2bbl, works fine. Those factory hot air tubes
>for the choke are nothing but a headache. They rust off at
>the exhaust manifold or fall off so your choke is sucking
>cold air. :-(
Yeah, the GM setup is much cleaner. The heat stove is built into the intake manifold just under the carb so it gets heat from the exhaust bypass. This also allows an intake tube that gets it's air from the carb air horn so it is filtered. On the downside, your bypass valve needs to be working properly and those are not so reliable over the long haul.
>short L shaped piece that is held by one bolt on the exhaust
>manifold. A short tube on the top uses aluminum flex to
>connect to the air cleaner. I use a Holley electric choke
>cap on my Ford 2bbl, works fine. Those factory hot air tubes
>for the choke are nothing but a headache. They rust off at
>the exhaust manifold or fall off so your choke is sucking
>cold air. :-(
Yeah, the GM setup is much cleaner. The heat stove is built into the intake manifold just under the carb so it gets heat from the exhaust bypass. This also allows an intake tube that gets it's air from the carb air horn so it is filtered. On the downside, your bypass valve needs to be working properly and those are not so reliable over the long haul.
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