Automatic Choke

[Ktga64]

I am writing to see if anyone has any ideas about how to replace the original automatic choke with a Sisson Choke, Model MC400. I purchased it NOS, but it has no instructions for installation or anything showing how it works. 

[Doug&Deb]

I’m not familiar with that choke unit. Do you have a choke on the car already? 49-52 Dodge and Plymouth used a choke that was opposite the unit on other Mopars. They’re much harder to find. Rich Hartung (deSoto1939) is the expert on this forum on Sisson chokes. Hopefully he’ll chime in.

[desoto1939]

I do not have any info on this choke can you take more pictures of the unit. So with the post with the nut there is an electrical feed and then it energizes something to make the choke butterfly close.

 

 

Rich Hartung

desoto1939@aol.com

[Ktga64]

Doug&Deb, the original chock is still on the manifold but I'm assuming that, at some point, it stopped working so the linkage was removed. When my father-in-law (now deceased) had the car "restored" the folks who did the job installed a manual choke linkage. All I can say is I believe my father-in-law got raped on this restore job, if you know what I mean. I have not taken the time to "fix" the manual linkage so that it will actually work. I figured I would try to restore the original operation but the automatic chokes (period specific), if you can find them are as much as a carb. Anyway, I found this Sisson and supposedly it's compatible but I can't figure out where it mounts and how it links to the carb. Thanks for the info on Rich (deSoto1939), I will try to touch base with him. 

[Ktga64]

2 hours ago, desoto1939 said:

I do not have any info on this choke can you take more pictures of the unit. So with the post with the nut there is an electrical feed and then it energizes something to make the choke butterfly close.

 

 

Rich Hartung

desoto1939@aol.com

Thanks for replying, I hear you are the subject mater expert on the Sissons. I will try to get more photos. I took several but with the 3mb limit, this photo was the only one that would upload. I'll have to see I I can reduce the pixels or something to get the photo size down below 3mb. More to follow...

[Doug&Deb]

Try attaching a wire to the original choke and touch it to the negative battery terminal ( assuming you have positive ground). If the choke still works the arm should rotate up slightly. If it works I’ll check to find the correct length for the linkage. I made my linkage for my Coronet and it works fine.

[Ktga64]

?

[desoto1939]

I know there is a 400 model listed on Ebay but I have never really seen one on a car.

 

rich Hartung

[Ktga64]

Yea, without a diagram or operating concept, I have no clue. It has nowhere to attach linkage. The description and the add on the packaging sounded good... hahaha

[Tom Skinner]

Contrary to what many may believe, If one is patient and a good Hunter one can still find Sisson Chokes on Ebay - often not listed a Sisson Choke but under other names.

I scooped up 2 for $14 a few years back. So hunting "Automotive Chokes" or "Vintage 1940's Auto Parts" or "1940's Mopar" or "Miscellaneous Mopar" may result in a hit.

I know I will hear the experts come on here and say it isn't so, but it is, because I have several Sisson Chokes in my Cabinet - on the Cheap.

So if paying $395 for a Sisson Choke is your thing, knock yourself out, but even at car shows in junk boxes they go for small money still.

Heck I bought a 1948 Chrysler Royal in 1973 for $600 with 32K miles on it. So I will never pay around $400 for a dinky Choke. That in my estimation is shear madness unless of course your loaded and don't care about being upside down in your car financially. Our old buses are only worth 8-18K in good running shape finished to begin with.

Why spend it all on a Choke. I'm sure I will hear why from the "Natering Nabobs of Negativism" (Spiro Agnew's favorite term) soon. LOL.

I won't argue back its not worth my time or energy. Believe what you want to believe. Even a manual Choke beats being raked over the coals for a Sisson.

 

[61spit]

It kind of looks like this is a choke that mounts on the side of the carburetor rather than on the manifold. Since there is no actuating arm to attach a linkage from this unit to the choke butterfly on the carburetor it makes me think it must mount directly to the butterfly arm on the side of the carburetor. May be for a span of years but only for certain carburetor? Since you said the original choke is still on the car I would look for one that matches it and replace it and the linkage from it to the carb.

[desoto1939]

1 hour ago, Tom Skinner said:

Contrary to what many may believe, If one is patient and a good Hunter one can still find Sisson Chokes on Ebay - often not listed a Sisson Choke but under other names.

I scooped up 2 for $14 a few years back. So hunting "Automotive Chokes" or "Vintage 1940's Auto Parts" or "1940's Mopar" or "Miscellaneous Mopar" may result in a hit.

I know I will hear the experts come on here and say it isn't so, but it is, because I have several Sisson Chokes in my Cabinet - on the Cheap.

So if paying $395 for a Sisson Choke is your thing, knock yourself out, but even at car shows in junk boxes they go for small money still.

Heck I bought a 1948 Chrysler Royal in 1973 for $600 with 32K miles on it. So I will never pay around $400 for a dinky Choke. That in my estimation is shear madness unless of course your loaded and don't care about being upside down in your car financially. Our old buses are only worth 8-18K in good running shape finished to begin with.

Why spend it all on a Choke. I'm sure I will hear why from the "Natering Nabobs of Negativism" (Spiro Agnew's favorite term) soon. LOL.

I won't argue back its not worth my time or energy. Believe what you want to believe. Even a manual Choke beats being raked over the coals for a Sisson.

 

Tom, I hear what you are saying. A friend of mine was a t last years Hershey swap meet and found a NOS in the Box with the gasket a Sisson Choke for a grand total of $10.  Yes they are out there but if a vendor knows what he has then the price will be what the vendor feels he can get for the item.  I know these units have gone up over the years.  So if you are searching for parts then you need to look at every vendor. Some time they really do not know what they have.

 

Last Sunday I was a t a local swap meet and vendor was selling NOS in the Box a sanp-on Sparkplug gapper tool. I have seen these on ebay and other places and they go for around 40-60 dollars.  we talked about the tool and i asked the gentleman what he was asking for it and he stated $5. I did not even think about the price.  Found another used one for $6.

 

Came home looked on ebay the same unit i just purchased was listed at $65.  Sometimes you get the prize and other time you have to pay for the prize. 

 

Rich Hartung

Desoto1939@aol.com

[Ktga64]

17 hours ago, desoto1939 said:

I know there is a 400 model listed on Ebay but I have never really seen one on a car.

 

rich Hartung

I have searched a little to try to find pics and/or diagrams but have been unsuccessful. I figured for $25 it was worth the shot in the dark. Another question. Can the orignial chokes be refurbished, if so, where would I start looking for replacement parts?

[Tom Skinner]

Try to get original parts to replace - especially - a Sisson Choke. They are simply the only way to go besides a manual one.

If you can find one and it works great! I don't know anything about rebuilding them. I took one apart a long time ago, liked to never got it put back together.

The winding in the top resembles a starter solenoid winding, virtually impossible to repair - for a electrical idiot like myself, a must needs replacing type situation as my best guess. 

[Doug&Deb]

I don’t believe they are rebuildable. Have you tried a wire directly to the choke? They don’t usually go bad. Oftentimes the studs on the manifold break or the bottom of the choke rusts away. To be wired correctly there should be a wire from the starter to the choke. It only activates when the starter is engaged. Is your choke mounted in front of the carb or behind? The front mounted is harder to find as it was only used on Plymouth and Dodge 49-52.

[Ktga64]

19 hours ago, 61spit said:

It kind of looks like this is a choke that mounts on the side of the carburetor rather than on the manifold. Since there is no actuating arm to attach a linkage from this unit to the choke butterfly on the carburetor it makes me think it must mount directly to the butterfly arm on the side of the carburetor. May be for a span of years but only for certain carburetor? Since you said the original choke is still on the car I would look for one that matches it and replace it and the linkage from it to the carb.

Yea, that's what it looks like to me too. I found original chokes, it's just... am I willing to pay the price for it. I will probably end up fixing the manual choke and going with that until I can do something different. I don't know who the guys were that my father-in-law employed to restore the car (10+ years ago) but, from what I've seen I wouldn't call them professionals. The manual choke cable is held up approximately 8" with metal strapping, you can imagine what happens when you push/pull the choke inside the car... absolutely nothing because the strap is not rigid enough to do it's job. Took Chrome off to paint, the side molding now stands about an 1/8" to 1/4" off the body of the car, completely left the windshield chrome off (I found a complete windshield chrome set a while back just haven't put it on yet). All-in-all, the car looks decent, just needs some TLC. Thanks for your input on my inquiry.

[pflaming]

I have three sisson chokes from parts car i bought. PM me and one of them may be yours at a fair price. I’m down sizing so things wlll go. 

[desoto1939]

KTGA64:  This is Rich hartung  got your PM. The picture of the 400 Sisson choke is one that is more like the modern choke that is part of the carb and built into the unit. There isa mounting ring and gaskets.  This is not going to work on your car.  Ther sisson choke that you show on your car is the correct one for 49-52 becasue it it mounted in front of the carb versus being mounted behind the carb.  The ones that mount in front are more costly as you have already discovered.

 

My next question is do you know how to setup the sisson choke that is currently on your car? I have the instructions and can walk you through the setup steps. It is not hard but also you are missing the rod that moves the choke butterfly closed.  I also have a document on the rod lengths and the measurements and how they are bent to conform to the linkage.

 

Once you get them set they are very reliable, i help doug and deb get their tested and got them to reuse theirs. They stopped by at my vendor site at Hershey this past october.  If you have a motors repair manual or even the one for your car it will go through the setup  steps.

 

Call me if you need some help.

 

Also can you attach some pictures of your current carb setup so we can see how they setup the manual choke?

 

Rich Hartung

desoto1939@aol.com

cell 484-431-8157

Home 610-630-9188

[kencombs]

On 3/6/2022 at 4:06 PM, Ktga64 said:

I am writing to see if anyone has any ideas about how to replace the original automatic choke with a Sisson Choke, Model MC400. I purchased it NOS, but it has no instructions for installation or anything showing how it works. 

Judging from the part of the box visible in the background, this looks like a replacement for the typical round choke used on a lot of Carter carbs.  .There is one on ebay whose pic shows the mounting ring.   Typical 3 screw mount similar to carters.  This may be a replacement for them to replace the exhaust heated one.

 

Just a guess.

[Dodgeb4ya]

I would think a good used choke hopefully reasonably priced is the way to go.

pflaming has offered up..I would try that route.

You will need the special insulated asbestos gasket that goes under it too.

[desoto1939]

OK on Ebay there is a new listing or posting for the same choke with the instruction sheet:

NOS 1946-1956 Ford, Lincoln, GM carburetor electric choke kit, Sisson

Suggest that you might try to contact the seller to see if he would scan or copy the install sheet for you and tell him your situation.

 

In the lisiting it states 48-50 Mopar, GM, ford Lincoln and other cars. I can see a picture in the instruction shhet that shows how the unit is attached to a carb just like the Delco units where your roates the outer black plastic to adjust the carb

 

Rich Hartung

Desoto1939@aol.com