Dodge RamCharger Central banner
1 - 3 of 3 Posts

·
Registered
Joined
·
8,249 Posts
Discussion Starter · #1 ·
1974 Plymouth Duster : 1970 340 with a 484 Purple Cam.

Reconnected the Vacuum Line i pulled off when i was messing with my stereo and the car had working A/C (parked in front of the garage, running at Fast Idle)

Works ok for a short while (when driving) then it starts blowing Warm Air (i'm thinking it's a mixture of Heat and A/C) on Max A/C or A/C because it fluctuates a bit between Cool and Warm, and the Evaporator continues to produce Water inside the Heater Box.

Climate Control holds vacuum long after the engine has been shut off, i can go out an hour from now and it's still holding vacuum. A/C System is charged with 134A, No Leaks.

I'm thinking that when the Vacuum drops (Shifting Gears, ect) it opens the Heater Valve and then starts blowing a mixture of Heat & A/C. If i shut the Climate Control Off for a second and turn it back to A/C it starts blowing Cold air again.

Was there a Check Valve anywhere in the Climate Control System on these cars?  Should i add one? Do you think that's what's happening? (vacuum drops and it opens the Heater Valve?)
 

·
Registered
Joined
·
29,317 Posts
l,d use a vacuum ball off a CAD system as a reserve and the the check valve
 

·
Registered
Joined
·
8,249 Posts
Discussion Starter · #3 ·
DODGEBOYS said:
l,d use a vacuum ball off a CAD system as a reserve and the the check valve
I have the factory Vacuum Resevoir/Ball on the car, but i'll add a Check Valve
 
1 - 3 of 3 Posts
Top