AC Issue
Thread Starter
Instructor
Joined: Oct 2006
Posts: 134
Likes: 0
From: Tulsa OK
AC Issue
1970 Vert. I have a dilemma. Rebuilt compressor. Stayed original with R12. Replaced heater control valve as it wasn't staying shut allowing coolant to run through heater core when AC Controls were set on Max.
New heater control valve still not closing.
My air out the passenger vent is still about 10 degrees above what the manuals say it should be which if you are in Oklahoma like I am is huge.
I've read the posts on installing a shutoff valve in the heater line. Certainly an option.
May be a vacuum issue? Should the valve be working at idle or do the RPM's need to be greater than idle to make the valve close?
Thanks in advance for any advice or assistance!
New heater control valve still not closing.
My air out the passenger vent is still about 10 degrees above what the manuals say it should be which if you are in Oklahoma like I am is huge.
I've read the posts on installing a shutoff valve in the heater line. Certainly an option.
May be a vacuum issue? Should the valve be working at idle or do the RPM's need to be greater than idle to make the valve close?
Thanks in advance for any advice or assistance!
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
The valve works at any engine rpm. The vacuum for all accessories using vacuum (wiper door, headlights, hvac) is supplied by a buffer tank tucked away on the right fender. You can test the valve with a hand-held vacuum pump to see if the problem is the valve or your vacuum supply.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
The AIM has a diagnostics page in the C60 options section which might be helpful in chasing down the problem.
Burning Brakes
Joined: Aug 2007
Posts: 891
Likes: 243
From: Green Valley Ca
Have you checked the seal around the two lines on heater core were they pass thru the A/C Heater Housing. And the damper door at passenger side cowl. Which closes when the A/C is on.
Bob
Bob
Thread Starter
Instructor
Joined: Oct 2006
Posts: 134
Likes: 0
From: Tulsa OK
Just got my AIM manual yesterday and still trying to get familiar with it but will try to find the page. Thanks!
Thread Starter
Instructor
Joined: Oct 2006
Posts: 134
Likes: 0
From: Tulsa OK
The valve works at any engine rpm. The vacuum for all accessories using vacuum (wiper door, headlights, hvac) is supplied by a buffer tank tucked away on the right fender. You can test the valve with a hand-held vacuum pump to see if the problem is the valve or your vacuum supply.
