Automotive Air Conditioning Information Forum (Archives)

Provided by

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

V7 Control Valve Position

72crew on Mon September 17, 2012 6:54 PM User is offline

Hi All,

I'm working on mounting a V7 compressor in my vintage application and have read on this forum and elsewhere that the control valve needs to be mounted in the 6 o'clock position (or close to it). This makes my mounting scenario more difficult even looking at all the different case designs that are available. While searching around I found these two different compressors from the same manufacturer for the same application (late 90's early 00's corvette) with the control valves in different positions. I called the MFG. tech line and was told that the two compressors are from two different sources and it didn't matter what orientation the valve was placed.

I haven't been able to find any information on the exact operation of this valve but I assume the pressure in the rear head moves a plunger against a spring to channel something to move the swash plate. If this is the case, why would it make a difference where it was located? Can someone explain why it would or wouldn't be necessary to locate it on the bottom?

Thanks for the help

GM Tech on Mon September 17, 2012 8:00 PM User is offline

The control valve position makes no difference- but it is the only external e"asy to use" reference for making sure the guide pin and shoe assemblies inside the compressor (also at 6 o'clock) are running under oil- or at least in an oil bath- so the max deviation from six o'clock would be about 30 degrees- as in the mounting on a 3.1L GM engine in mid 90's--the control valve was at the 4:30 or so position. There is a nominal amount of oil retained within the compressor crankcase- usually 3 ounces at any given time or condition. The goal is to keep the internals lubed well- the brass guide pin shoe is high supceptible to seizing if not enough lube- that why it is best to run it under the oil level. Go ahead and mount 30 degrees either direction and you will be fine- any more and you do chance early compressor failure- but who knows how long it would take? Under seldom use conditions, it may be several is your call....

The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

72crew on Mon September 17, 2012 11:19 PM User is offline

GM Tech,

Thanks for your detailed explanation - just what I needed to know. I do want a system that I don't have to mess with; so I will deal with my mounting situation and locate my compressor in a OEM orientation to assure proper lubrication. I guess with regard to the compressors above they probably just rotated the valve and not the components that require lubrication.


Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.