PROBLEM No heat in cockpit
Thread Starter
Pro
Joined: Jul 2004
Posts: 689
Likes: 1
From: Media PA
PROBLEM No heat in cockpit
69 Coupe, no AC. Have hot water to heater core, have good vacuum to
heater controls, but cool air coming out vents. Also when you select defrost you get increased air flow from windshield defrost vent, but no change to air flow at other vents. I get vacuum to diaphragm. Does anyone think air door is stuck inside air box and how do you fix it?
heater controls, but cool air coming out vents. Also when you select defrost you get increased air flow from windshield defrost vent, but no change to air flow at other vents. I get vacuum to diaphragm. Does anyone think air door is stuck inside air box and how do you fix it?
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Originally Posted by rtpilot
69 Coupe, no AC. Have hot water to heater core, have good vacuum to
heater controls, but cool air coming out vents. Also when you select defrost you get increased air flow from windshield defrost vent, but no change to air flow at other vents. I get vacuum to diaphragm. Does anyone think air door is stuck inside air box and how do you fix it?
heater controls, but cool air coming out vents. Also when you select defrost you get increased air flow from windshield defrost vent, but no change to air flow at other vents. I get vacuum to diaphragm. Does anyone think air door is stuck inside air box and how do you fix it?
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
If its cable or vacuum related. It repairable. you may need to open the core box to do it. make sure you are getting water through the core as mentioned.
BTW My 82 has a vacuum controlled stop valve on the hose in the engine compartment area...not sure yours has the same.
Jim
BTW My 82 has a vacuum controlled stop valve on the hose in the engine compartment area...not sure yours has the same.
Jim
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Safety Car
Joined: Jun 2002
Posts: 4,135
Likes: 1
disc one vaccume accuator at a time ,take a short vaccume hose ,and temp run a vaccume to each accuator,and see if they operate....if they do ,,and do not at the selector ,,then trouble shoot the selector(vaccume porta switch)if it does not work ,,then make sure the vaccume line(feed) has vaccume ....1 vaccume hose (black =no tracer)is the source or feed ,,,the rest are loads to each accuator(they have tracers)red ,green, ect ...if alll this works ,then its the cable not opening the door--------------------------------------------
Safety Car
Joined: Jun 2002
Posts: 4,135
Likes: 1
Originally Posted by rtpilot
Checked vacuum lines to heater box and the are OK with no leaks. Cannot hear door moving in air box. Any way to fix?
Thread Starter
Pro
Joined: Jul 2004
Posts: 689
Likes: 1
From: Media PA
Originally Posted by jackson
Understand you have hot water TO core ... but do you have hot water THROUGH it and OUT of it? If core is stopped up ... the air will not get hot. First, suggest you verify if you have full flow of water THROUGH core ... you can pull the hoses off and push water to it from a garden hose ... if water IN & water OUT ... core's ok ... easy check. BTW ... if ever there's been radiator "stop leak" stuff put in system ... it tends to collect in heater core & clog/plug it up.
free the doors? Thanks
Burning Brakes
Joined: Aug 2005
Posts: 1,126
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From: Hudson Falls, N.Y. 76 Vette Modified L-48
Originally Posted by jackson
Understand you have hot water TO core ... but do you have hot water THROUGH it and OUT of it? If core is stopped up ... the air will not get hot. First, suggest you verify if you have full flow of water THROUGH core ... you can pull the hoses off and push water to it from a garden hose ... if water IN & water OUT ... core's ok ... easy check. BTW ... if ever there's been radiator "stop leak" stuff put in system ... it tends to collect in heater core & clog/plug it up.
Racer
Joined: Jul 2004
Posts: 408
Likes: 0
From: Buffalo NY
That drawing was for a 73 with AC, the 69 without AC is different.
Make sure your temperature selection cable is moving the arm that moves the flap inside the heater box.
Are you supposed to be able to get heat out of the dash vents on a non AC car? I had mine apart the weekend and there were only 2 actuators, one to change from the defroster to the floor vents, and a second towards the middle of the box. What is the second actuator do, and when should it have vacuum on it?
Make sure your temperature selection cable is moving the arm that moves the flap inside the heater box.
Are you supposed to be able to get heat out of the dash vents on a non AC car? I had mine apart the weekend and there were only 2 actuators, one to change from the defroster to the floor vents, and a second towards the middle of the box. What is the second actuator do, and when should it have vacuum on it?
Last edited by matthud; Dec 6, 2005 at 01:32 PM.
Thread Starter
Pro
Joined: Jul 2004
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From: Media PA
The temp cable is moving the arm for the temp door. It seems the vacuum door controlled by the control on the left side of the heater control does not have any effect except to open the windshield defrost. My question is , can the air box be opened to fix stuck door or can the vacuum control on the air box be replaced?
