Another Thermoquad Carb Question

[gerahead]

It seems the puzzle continues! The thermoquad that I have for the 340 in my project has an electric choke similar to those used on the General's cars. I am still trying to figure out this assembly puzzle. I have found a schematic for the 73 Challenger engine harness that I was told the engine came from. The schematic shows a choke controller component. What does this component look like and how is it mounted?
Another, simpler question . . . . the carb's fuel inlet fitting is missing. What does this fitting look like? I am trying to put this project back together as close to original as I can, given that nothing about it is original, if that makes sense! The photo is reference to what I am working with. Thanks again guys!

Jim

 

[RustyRatRod]

Choke controller or choke timer. Looks similar to this.

Pardon Our Interruption...

 

[halfafish]

What TQ number are you working on, and can you post a photo of where the fuel inlet would go? I have a handful of TQ parts carbs, I can probably get you the missing piece.

 

[Vaanth]

It seems the puzzle continues! The thermoquad that I have for the 340 in my project has an electric choke

View attachment 1716446194

The pictured Thermo-Quad is an aftermarket Super-Quad, either a 9801S or 9811S. It's not an original Chrysler equipped carburetor. The aftermarket 9000 series Super-Quads were available in four models: 9801, 9811, 9800, and 9810. The 9801 and 9811 have Chrysler linkage. The 9800 and 9810 have GM linkage. The GM linkage can be adapted to Chrysler applications. The 9810 and 9811 have a venturi fuel bowl mounted vacuum signal port for EGR applications, which can be capped if not used.

The following image shows one of my Super-Quads:

I have found a schematic for the 73 Challenger engine harness that I was told the engine came from. The schematic shows a choke controller component. What does this component look like and how is it mounted?

The Chrysler electric choke control was used on all 1973 - 1984 carbureted vehicles that used the electric assist heated divorced choke. The electric choke control adjusts the rate and time of power applied to the choke thermostat. The control allowed quicker warm-up for sooner choke release above 68 degrees Fahrenheit, and slower warm-up below that temperature. After two to three minutes, the control shuts off the power to the choke thermostat heating element. A single stage and dual stage unit was used. Dual stage units have a finer temperature control and have an external resistor mounted. The style of construction changed in 1977.

The electric control is a small module mounted to the intake or head. The four styles of electric control units are listed in the following and shown in the following image:

• Chrysler 3656730, 3698357: 1973-1976 single stage.
• Chrysler 3755750, 3755770: 1974-1976 dual stage.
• Chrysler 4049799: 1977-1984 single stage.
• Chrysler 4049777, 4091034: 1977-1984 dual stage.

The controller is mounted on the intake manifold on small blocks or on the head on big block and slant six engines. The following image shows one mounted:

The controller was not used for the aftermarket Super-Quads with the integral electric choke, but it will work with one. I have been using a 1973 vintage control on my 340 with a Super-Quad for over 20 years.

Another, simpler question . . . . the carb's fuel inlet fitting is missing. What does this fitting look like? I am trying to put this project back together as close to original as I can, given that nothing about it is original, if that makes sense! The photo is reference to what I am working with. Thanks again guys!

Jim

View attachment 1716446194

The original style fuel fitting is the same for all 1971- 1984 Chrysler applications. Similarly for International Harvester applications, but the Ford applications differ. The standard fitting for Thermo-Quads installs into the body with 5/8-30 pipe thread using a 3/4" hex. The fuel line attaches using a 5/16-20 inverted flare fitting (1/2-20 thread). An aftermarket similar replacement version is available from Walker as part number 90-43. The fittings are originally installed with a rubber coated aluminum shim gasket. Aftermarket replacements may be a fiber washer.

The following image shows the original fitting:

 

[gerahead]

The pictured Thermo-Quad is an aftermarket Super-Quad, either a 9801S or 9811S. It's not an original Chrysler equipped carburetor. The aftermarket 9000 series Super-Quads were available in four models: 9801, 9811, 9800, and 9810. The 9801 and 9811 have Chrysler linkage. The 9800 and 9810 have GM linkage. The GM linkage can be adapted to Chrysler applications. The 9810 and 9811 have a venturi fuel bowl mounted vacuum signal port for EGR applications, which can be capped if not used.

The following image shows one of my Super-Quads:
View attachment 1716446270



The Chrysler electric choke control was used on all 1973 - 1984 carbureted vehicles that used the electric assist heated divorced choke. The electric choke control adjusts the rate and time of power applied to the choke thermostat. The control allowed quicker warm-up for sooner choke release above 68 degrees Fahrenheit, and slower warm-up below that temperature. After two to three minutes, the control shuts off the power to the choke thermostat heating element. A single stage and dual stage unit was used. Dual stage units have a finer temperature control and have an external resistor mounted. The style of construction changed in 1977.

The electric control is a small module mounted to the intake or head. The four styles of electric control units are listed in the following and shown in the following image:

• Chrysler 3656730, 3698357: 1973-1976 single stage.
• Chrysler 3755750, 3755770: 1974-1976 dual stage.
• Chrysler 4049799: 1977-1984 single stage.
• Chrysler 4049777, 4091034: 1977-1984 dual stage.

View attachment 1716446259

The controller is mounted on the intake manifold on small blocks or on the head on big block and slant six engines. The following image shows one mounted:
View attachment 1716446267

The controller was not used for the aftermarket Super-Quads with the integral electric choke, but it will work with one. I have been using a 1973 vintage control on my 340 with a Super-Quad for over 20 years.




The original style fuel fitting is the same for all 1971- 1984 Chrysler applications. Similarly for International Harvester applications, but the Ford applications differ. The standard fitting for Thermo-Quads installs into the body with 5/8-30 pipe thread using a 3/4" hex. The fuel line attaches using a 5/16-20 inverted flare fitting (1/2-20 thread). An aftermarket similar replacement version is available from Walker as part number 90-43. The fittings are originally installed with a rubber coated aluminum shim gasket. Aftermarket replacements may be a fiber washer.

The following image shows the original fitting:
View attachment 1716446260

Vaanth,
This is extraordinary information, thanks for the accompanying photos for illustration! With respect to the choke question, if I use the choke mechanism as it exists, what is the source for the power for this aftermarket carb? Is it the same as the system with the controller? If I choose to use the OE style choke system, from the pic it looks like I would just need to remove the aftermarket choke mechanism from the carb and install the divorced choke stove and the controller. Is that correct? Thanks again for another thorough response to my newbie questions!

 

[gerahead]

What TQ number are you working on, and can you post a photo of where the fuel inlet would go? I have a handful of TQ parts carbs, I can probably get you the missing piece.

halfafish,
My carb number is 9801S and the fuel inlet is located in the top, rear, passenger side of the casting (circled in photo). I am also using a reproduction of the OE fuel line from the pump. after your response, Vaanth also replied to this thread with a photo of what the inlet fittings look like. Thanks.

Jim

 

[Vaanth]

Vaanth,
This is extraordinary information, thanks for the accompanying photos for illustration! With respect to the choke question, if I use the choke mechanism as it exists, what is the source for the power for this aftermarket carb? Is it the same as the system with the controller?

Yes, it is the same power source, which was originally wired into the Ignition Run circuit, before the ballast resistor (typically the blue wire on passenger cars). Any similar switched 12 volt source will work though.

If I choose to use the OE style choke system, from the pic it looks like I would just need to remove the aftermarket choke mechanism from the carb and install the divorced choke stove and the controller. Is that correct? Thanks again for another thorough response to my newbie questions!

The integral choke can be replaced with the factory style divorced choke, The choke shaft lever differs, so some adjustment of the choke rod, or swapping the lever with another that is removable, for choke plate shaft might be needed.

The following image shows a comparison of the Super-Quad integral choke with a 1972 Thermo-Quad and integral choke.

The levers changed some among the different years and models. The following images show a Super-Quad choke, a 1972 Thermo-Quad choke setup and a later Thermo-Quad with a different lever choke setup:

 

[halfafish]

My carb number is 9801S and the fuel inlet is located in the top, rear, passenger side of the casting (circled in photo).

Good info, and as always a hats-off to @Vaanth for stellar info. Give me a day or so to root through my pile of parts carbs. My shop is a disaster at the moment so it will take a little fiddling to get to that box.

 

[gerahead]

Yes, it is the same power source, which was originally wired into the Ignition Run circuit, before the ballast resistor (typically the blue wire on passenger cars). Any similar switched 12 volt source will work though.


The integral choke can be replaced with the factory style divorced choke, The choke shaft lever differs, so some adjustment of the choke rod, or swapping the lever with another that is removable, for choke plate shaft might be needed.

The following image shows a comparison of the Super-Quad integral choke with a 1972 Thermo-Quad and integral choke.
View attachment 1716446342

The levers changed some among the different years and models. The following images show a Super-Quad choke, a 1972 Thermo-Quad choke setup and a later Thermo-Quad with a different lever choke setup:
View attachment 1716446345
View attachment 1716446344
View attachment 1716446343

Awesome info Vaanth! I thought that this was going to be a very straight forward, clean up and re-install project! It looks like I have the latter (the one directly above) style choke linkage. I had already sourced the non-electric divorced choke, so maybe it will be a direct replacement. I guess I have more work to do!

 

[gerahead]

Good info, and as always a hats-off to @Vaanth for stellar info. Give me a day or so to root through my pile of parts carbs. My shop is a disaster at the moment so it will take a little fiddling to get to that box.

Thank you sir!

 

[halfafish]

Thank you sir!

Whoops! Lost sight of this for a bit. Do you still need the fitting? I can finally get to my pile of TQ's if needed.

 

[lemondana]

Use the original electric choke on the 9801 carb. They work flawlessly when adjusted correctly. I just run one wire to the keyed 12 volt side of the ballast resistor.

 

[lemondana]

Forget all of that other heating element and switch, you don't need it with the OE choke on the 9801 carb!

 

[gerahead]

Whoops! Lost sight of this for a bit. Do you still need the fitting? I can finally get to my pile of TQ's if needed.

Yessir, I do!! No worries, I have been out of town for the last 10 days. Thanks

 

[gerahead]

Use the original electric choke on the 9801 carb. They work flawlessly when adjusted correctly. I just run one wire to the keyed 12 volt side of the ballast resistor.

Forget all of that other heating element and switch, you don't need it with the OE choke on the 9801 carb!

Lemondana,
I don't have the OE electric choke. I am just trying to figure out the easiest way to make what I have work. What you're suggesting is what I was thinking. Thanks!

 

[DionR]

I ran that 9801 style choke setup on my R/T headed LA because the dual plane M1 intake didn't have a choke well for the stock type. Had to build a mount to support the choke and then hunted high and low to get a good cover. But once I had everything, it worked well.

 

[lemondana]

Is the picture of the TQ in your first post what you have? Just without the round choke cap? They are available on Ebay-Carter 170-1322 39.95. auction number 388831798730, 7 available. If you need the retaining ring-QuadrajetParts.com has them and the gasket and screws.

 

[DionR]

Is the picture of the TQ in your first post what you have? Just without the round choke cap? They are available on Ebay-Carter 170-1322 39.95. auction number 388831798730, 7 available. If you need the retaining ring-QuadrajetParts.com has them and the gasket and screws.

Is that pointed at me?

I looked for years for that cap. I had something someone had soldered a wire to that came apart and then bought a junk TQ with a good choke cap on it at a swap meet. Pure luck. Before that I couldn't find anything. Zero, zilch.

BTW, the picture in my post is prior to finding a good cap.

I've since put the TQ on the shelf and run an Edelbrock. I have a Hughes EFI intake on the motor with the injector ports plugged because I planned to run Magnum EFI and swapped the intake when I was putting a cam in it but wasn't ready to make the EFI conversion. But now I'm not sure if I will ever EFI it since I have a G3 swap car in the works.

 

[lemondana]

Is that pointed at me?

I looked for years for that cap. I had something someone had soldered a wire to that came apart and then bought a junk TQ with a good choke cap on it at a swap meet. Pure luck. Before that I couldn't find anything. Zero, zilch.

BTW, the picture in my post is prior to finding a good cap.

I've since put the TQ on the shelf and run an Edelbrock. I have a Hughes EFI intake on the motor with the injector ports plugged because I planned to run Magnum EFI and swapped the intake when I was putting a cam in it but wasn't ready to make the EFI conversion. But now I'm not sure if I will ever EFI it since I have a G3 swap car in the works.

No, the first post in this column. These TQ Chokes have been on Ebay for a long time. and they are different that other chokes. They are wound the opposite way. The Carter 170-1322 is the only correct one.

 

[gerahead]

No, the first post in this column. These TQ Chokes have been on Ebay for a long time. and they are different that other chokes. They are wound the opposite way. The Carter 170-1322 is the only correct one.

I'm assuming that my first post is the one you're referring to. Yes, the carb shown in the very first pic of this thread is the exact carb that I have for my project.

 

[lemondana]

This Carter 170-1322 choke is what you want then.

 

[M_Body_Coupe]

Use the original electric choke on the 9801 carb. They work flawlessly when adjusted correctly. I just run one wire to the keyed 12 volt side of the ballast resistor.

Lemondana,
I don't have the OE electric choke. I am just trying to figure out the easiest way to make what I have work. What you're suggesting is what I was thinking. Thanks!

What I think was meant by this statement is that you should use the electric choke that the 9801 carb is equipped with...so literally the black choke housing you show in your original photo.

Note the following: the early (1976) Carter instructions provide the incorrect choke height setup (measured from the base of the carburetor to the linkage hole in one of the choke brackets - this is actually well explained in the instructions once you read them, but the measurement they provide is FAR too short).

I struggled with this for a very LOOONNNGGGG time and only through experimentation I finally arrived at the correct setup. The icing on the cake was when Vaanth posted the updated 1981 instructions on this site (HERE) which does show the correct dimensions. Follow this setup to the letter as the TQ adjustments need to be done in sequence, else things get out of whack!

For what it's worth: Vaanth's scan is nice, but if your eyes are like mine by the time you print this as you head into the garage things do look awfully small...lol

So, I took to a bit of visual/image clean-up, scanning and re-scanning until I produced something that made me happier and sort of matched the original 1976 Carter instructions scans (although the quality is a bit lower, of course)...take a look please:

1) Original 1976 Carter Service Instructions (9800)
2) Updated 1981 Carter Service Instructions (9800 & 9801)

BTW - just in case you do not know this, the 9800 & 9810 use GM throttle linkage and 9801 & 9811 use Chrysler linkage...the GM stuff is easy to convert to our Mopar stuff, unless you already run something like a Lokar/cable setup.

 

[gerahead]

What I think was meant by this statement is that you should use the electric choke that the 9801 carb is equipped with...so literally the black choke housing you show in your original photo.

Note the following: the early (1976) Carter instructions provide the incorrect choke height setup (measured from the base of the carburetor to the linkage hole in one of the choke brackets - this is actually well explained in the instructions once you read them, but the measurement they provide is FAR too short).

I struggled with this for a very LOOONNNGGGG time and only through experimentation I finally arrived at the correct setup. The icing on the cake was when Vaanth posted the updated 1981 instructions on this site (HERE) which does show the correct dimensions. Follow this setup to the letter as the TQ adjustments need to be done in sequence, else things get out of whack!

For what it's worth: Vaanth's scan is nice, but if your eyes are like mine by the time you print this as you head into the garage things do look awfully small...lol

So, I took to a bit of visual/image clean-up, scanning and re-scanning until I produced something that made me happier and sort of matched the original 1976 Carter instructions scans (although the quality is a bit lower, of course)...take a look please:

1) Original 1976 Carter Service Instructions (9800)
2) Updated 1981 Carter Service Instructions (9800 & 9801)

BTW - just in case you do not know this, the 9800 & 9810 use GM throttle linkage and 9801 & 9811 use Chrysler linkage...the GM stuff is easy to convert to our Mopar stuff, unless you already run something like a Lokar/cable setup.

Thanks for the reply, I think that I had interpreted the comment correctly. What I was meaning is that I did not have the OE style (as opposed to this aftermarket carb version) electric choke that sits into the well on the intake manifold. The additional information will be helpful, for sure!

Jim