1974 A/C not cooling in cab
Thread Starter
7th Gear
Joined: Sep 2004
Posts: 7
Likes: 0
1974 A/C not cooling in cab
A tricky problem with our 1974 Stingray. The compressor kicks in and is freezing on the low side, and the high side has normal pressure. The heater is pinched off but the cool air never reaches the cab. The cold/hot air door is closing and opening fine because we can hear it. There are no leaks in the system and the system has the right amount of freon. Been thinking what could be wrong but can't get it. Has anybody had this problem before?? I know its a hot car but we want to be cool. 
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I'd bet there is a lot of leaves and debris covering the evaporator. There is really only one GOOD way to clean it and that's to pull the blower fan out and reach through it's hole and clean everything out.
While you're in there you will be able to see if the door is in fact opening properly.
While you're in there you will be able to see if the door is in fact opening properly.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
If the low side line is cold and you have good air flow thru the ducts but no cold air that would indicate a temp control door not operating. Before you rip into the blower, go behind the dash and under the console to se whats what on the temp control
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Could it still be that way if there is no air flow from the vents? I would think air flow would have to be good to get the lower end cold but something is keeping air from coming out. I hope it's not a mouse nest in there aft of the door.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
The fan blows directly into the condensor, there is nothing in between. The ducts and doors are all on the other side of the condensor. I asumed from her post about good air flow that it meant at the dash. There may still be duct leaks and the temp control door may be alowing to much warm air to mix with the cold off the condensor
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
The fan blows directly into the condensor, there is nothing in between. The ducts and doors are all on the other side of the condensor. I asumed from her post about good air flow that it meant at the dash. There may still be duct leaks and the temp control door may be alowing to much warm air to mix with the cold off the condensor
I guess it all hinges on if ANY air is coming out or not. I was also thinking of the nest or possible blockage being after the evap in the ducting.
