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PLEASE HELP!!! Heater box motor names

Bob Jordan

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Pinckney, MI
I know I have posted this twice but I am under the dash and I need help
Thank you and that was very helpful but I need a little more help. I know it should be obvious but I can't figure it out. I have the correct hoses going to the far right motor. I don't know the names of the two vacuum motors on the LEFT (driver side) of the heater box. Which is the defrost/heat motor and which is the heat/cool motor? Can someone just tell me which of those is closest to the FRONT of the car? I am literally under the dash trying to get this ready to go to the trim shop.
 
Could someone PLEASE PLEASE PLEASE post a picture of the heater assembly and label the three vacuum motors. PLEASE!
 
thanks again for trying to help but that is NOT a plymouth heater box it is a chrysler and the two left side motors are completely different.
 
I looked in my 1964 shop manual, and all I could find was vacuum hose routing for factory A/C. I removed the heater from my car years ago and replaced it with a factory A/C unit from a U.S. parts car (A/C was not an option on Windsor-built cars). Over the years, this system failed, and I have replaced it with Vintage Air. I will look at shop manual again.
 
Yeah I know the FSM and the parts book is ZERO help for a non A/C car. I know the outside air inlet motor is on the far right hand (passenger) side so I can make sure I have the right hoses going to that. I'll hook the two up on the left side the way I think they should go and if it doesn't work properly I can swap them later. I REALLY just need to know the relative locations of the "defrost/heat" and "cool/heat" vacuum motors. No offense but the info on the 62-65 mopar site is SUPER confusing - it references defrost heat vacuum motor as "closest to rear of vehicle "but front of heater box for this discussion". Front is front and rear is rear.
https://1962to1965mopar.ornocar.org/ml-62-65heaters.html
 
Yeah I know the FSM and the parts book is ZERO help for a non A/C car. I know the outside air inlet motor is on the far right hand (passenger) side so I can make sure I have the right hoses going to that. I'll hook the two up on the left side the way I think they should go and if it doesn't work properly I can swap them later. I REALLY just need to know the relative locations of the "defrost/heat" and "cool/heat" vacuum motors. No offense but the info on the 62-65 mopar site is SUPER confusing - it references defrost heat vacuum motor as "closest to rear of vehicle "but front of heater box for this discussion". Front is front and rear is rear.
https://1962to1965mopar.ornocar.org/ml-62-65heaters.html
Closest to the front of the heater box would also be closest to the rear of the car. The rearmost motor, closest to the firewall, is also closest to the front of the car.
 
I am still confused as all hell. It would be so much easier if the front of the heater box was at THE FRONT OF THE CAR and the rear of the heater box was AT THE REAR OF THE CAR. If someone can post a picture with arrows naming the vacuum motors I will be in your debt forever. When I get this sorted out I will post what I will then KNOW is correct. And all but my engine manifold hose are either black with red tracer or black with white tracer.
 
Per the FSM, the top vacuum motor (closest to the firewall) operates the defroster door. The lower motor (closest to the front of the dash) operates the heater door.
 
Per the FSM, the top vacuum motor (closest to the firewall) operates the defroster door. The lower motor (closest to the front of the dash) operates the heater door.
Which FSM Dave? And is that for a non A/C car? I have read ALL the service manuals and that contradicts the info on the 62-65 site. That site states that for a non A/C car that the defroster door is closest to the REAR of the vehicle. I am losing my mind here.
 
Which FSM Dave? And is that for a non A/C car? I have read ALL the service manuals and that contradicts the info on the 62-65 site. That site states that for a non A/C car that the defroster door is closest to the REAR of the vehicle. I am losing my mind here.
FSM is 81-270-4250. The pictures I am quoting from are for A/C. I am assuming that motors are in same relative position for both systems. Are you able to disconnect one of the defroster hoses from the unit? Then operate the linkage by hand to see which one opens and closes the defroster door.
 
FSM is 81-270-4250. The pictures I am quoting from are for A/C. I am assuming that motors are in same relative position for both systems. Are you able to disconnect one of the defroster hoses from the unit? Then operate the linkage by hand to see which one opens and closes the defroster door.
Great idea I tried that. I disconnected the defroster hoses from the box and manually operated the plungers and could not find or feel a door moving. At this point I think I'll just lay under the dash here and freeze to death.
 
The rear left one, in is defrost, out is heat.
The flapper inside redirects the air to the 2 tubes for defrost. It actually flows up inside the cover, not pictured.
Bottom pic, 4 screws hold defrost flapper.

The front one on the left opens and closes the foot or lower vent for more or less heat.

Front and rear based on front and rear of car.

20220228_080515.jpg 20220111_194428.jpg
 
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I am still confused by front and rear. Please reference the names of the vacuum motors relative to the front and rear of THE CAR. Thank you!!!!!
 
So to match the nomenclature used elsewhere the bottom "flapper" door that you can SEE move is the cool/heat damper - right?
 
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