85 heater problem
Safety Car
Joined: Oct 2007
Posts: 4,426
Likes: 229
From: Pennsylvania
Sounds like the deflector door is not closing completely in the heater box under the passenger side dash. The cable probably came disconnected. Drop the carpeted panel under the dash on passenger side. Remove the ECM (electronic control module). It's the first thing you'll see there. Behind it is the heater box and you can inspect the cable connection there.
Safety Car
Joined: Aug 2009
Posts: 3,745
Likes: 275
From: Melbourne, Victoria, Australia
Hi
The vacuum controls the air delivery, routing the vacuum to the required location like demist to screen, floor and the 4 adjustable grilles to the cabin. You will have vacuum dampers opening and closing what is requied via the selector lever, Check your vacuum supply from the engine and confirm you can see the vacuum dampers open and close things like recirculation damper when a/c max is selected or the demist damper opens to let the airflow up to the windsheild.
The cable is manually adjusted by the temperature lever, the flap will open and close for heater or a/c airflow i believe. I have a shop manual at home i can post a diagram of how it all works when i get home.
Gerard
The vacuum controls the air delivery, routing the vacuum to the required location like demist to screen, floor and the 4 adjustable grilles to the cabin. You will have vacuum dampers opening and closing what is requied via the selector lever, Check your vacuum supply from the engine and confirm you can see the vacuum dampers open and close things like recirculation damper when a/c max is selected or the demist damper opens to let the airflow up to the windsheild.
The cable is manually adjusted by the temperature lever, the flap will open and close for heater or a/c airflow i believe. I have a shop manual at home i can post a diagram of how it all works when i get home.
Gerard
Thread Starter
Advanced
Joined: Feb 2014
Posts: 50
Likes: 0
Hi
The vacuum controls the air delivery, routing the vacuum to the required location like demist to screen, floor and the 4 adjustable grilles to the cabin. You will have vacuum dampers opening and closing what is requied via the selector lever, Check your vacuum supply from the engine and confirm you can see the vacuum dampers open and close things like recirculation damper when a/c max is selected or the demist damper opens to let the airflow up to the windsheild.
The cable is manually adjusted by the temperature lever, the flap will open and close for heater or a/c airflow i believe. I have a shop manual at home i can post a diagram of how it all works when i get home.
Gerard
The vacuum controls the air delivery, routing the vacuum to the required location like demist to screen, floor and the 4 adjustable grilles to the cabin. You will have vacuum dampers opening and closing what is requied via the selector lever, Check your vacuum supply from the engine and confirm you can see the vacuum dampers open and close things like recirculation damper when a/c max is selected or the demist damper opens to let the airflow up to the windsheild.
The cable is manually adjusted by the temperature lever, the flap will open and close for heater or a/c airflow i believe. I have a shop manual at home i can post a diagram of how it all works when i get home.
Gerard
Dennis
Safety Car
Joined: Aug 2009
Posts: 3,745
Likes: 275
From: Melbourne, Victoria, Australia
Hi
Here is some stuff to help you from my shop manual.
The vacuum goes from the engine and check valve thru the wiring harness, that will be the easiest to do that the check valve works and the vacuum ball holds a vacuum.
Of course the engine needs to run when checking the heater/ air conditioning controls.
Here is some stuff to help you from my shop manual.
The vacuum goes from the engine and check valve thru the wiring harness, that will be the easiest to do that the check valve works and the vacuum ball holds a vacuum.
Of course the engine needs to run when checking the heater/ air conditioning controls.
Thread Starter
Advanced
Joined: Feb 2014
Posts: 50
Likes: 0
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