what is this?

[JPP]

I am new to Dodge and my 1950 B2B, what is this attached to my manifold.  I has a lever for a push pull knob, what does it do and how do I use it?  the carburetor has a manual choke.  Thanks 

[Reg Evans]

That is your sisson automatic choke.

[JBNeal]

your engine might be a replacement rebuild out of a car; the flathead in my early '48 is out of a '55 Plymouth...

additional information - flathead identification 

Edited August 27, 2021 by JBNeal
revised link

[JPP]

Ok, so I have two chokes? Which one do I use? Do I use them both? Close on start the open after engine warms up? Thanks

[Don Coatney]

Might be a throttle cable, might not.

[JPP]

Not a car engine has a TT number, that matches can and frame dates. I knew original owner. So do I need a nob and cable to make this work?

[Dodgeb4ya]

The exhaust manifold has probably been replaced with a car exhaust that uses the automatic sisson choke... noticed the wrong nuts and washers on the exhaust manifold.

The trucks use a dash operated knob and cable type choke.

[Merle Coggins]

Maybe someone replaced the manifolds sometime in the past. It certainly appears to be an automatic choke setup. Your truck wouldn't have had that originally.

Merle

[JPP]

So what does the linkage between the sisson auto choke and the carb look like? Does anyone have a picture.

[_shel_ny]

Rods came in different lengths for different application.

 

You will not need 2 chokes.

 

 

EDIT:  Sisson choke is electrical. It is just a solenoid that is energized when starting. A wire would run from the starter to the screw on the sisson choke providing power to it anytime you are cranking the engine. There is a bi-metallic spring in the base that when warmed up changes how much the sisson closes the plate in the carb. Full closed when cold start, and gradually reduces how much it is closed depending upon how hot the engine/manifold is.

 

The position that the choke is mounted (forward of the carb) leads me to believe the manifold is a 49 and up. My 48 was mounted rearward of the carb. My 51 was forward.

Edited January 2, 2016 by shel_ny

[greg g]

The can is a stove.  Inside there is a bi metallic strip.  The choke butterfly will close when cold when the acc pedal is floored.  This will set it in cold position.  As the manifold gets hot, the bi metallic strip will react to the heat to pull the choke open and hold it in open position.  For the hand choke, typically you will pull it closed start the truck and adjust it in increments till the engine is up to operating temp.  There may also be a throttle cable that will allow you to adjust the idle speed during the warm up process.  

[_shel_ny]

Meanwhile back to the incorrect manifold nuts as pointed out by Dodgeb4ya.

 

This thread will shed some light on that:

 

http://p15-d24.com/topic/39236-got-a-good-start-on-the-exhaust-fix-today-need-some-help/?hl=%2Btapered+%2Bnut#entry413445

[JPP]

Great, thanks for the details. I am going to fab my own rods, once I get the engine running I will have more questions.

[desoto1939]

the sisson choke came from the 49-55 Plymouth. The Plymouth in 49 moved the sisson choke to be in front of the carb. the 35-55 Chrysler Dodge and Desoto had the sisson choke behind the carb.  I can also tell but the little slit that is on the base of the body of the choke and how the arm is on the choke body.  The late plymouth choke is not interchangeable with the early models.

 

I have the adjustment catalog of these chokes.  I might be off on the ending years but in 49 Plymouth started using this style of the sisson choke.

 

Rich Hartung

Desoto1939@aol.com