Automotive Air Conditioning Information Forum (Archives)

77shovelhead on Tue August 10, 2010 4:54 PM

Year: 95
Make: Olds
Model: 88 Royale
Engine Size: 3.8
Refrigerant Type: 134
Country of Origin: United States

I screwed up and didn't pull the switch out of the old compressor before turning it in.

I picked up a new one.

Now, I don't know which hole it goes in. There are two holes and I have a 50/50 chance to guess.

Using the Mastercool service manual, I figure the compressor is a Harrison HR-6 6-cylinder.

Page 218 fig. 16, shows the back side of the compressor. Is that the switch in the bottom right hole, under the discharge port?

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Quality is never an accident it is always the result of intelligent effort.

TRB on Tue August 10, 2010 6:39 PM

I believe you can use either port. GMTech will probably know for sure.

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When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

GM Tech on Tue August 10, 2010 9:17 PM

They are both high side communication ports-- use either one....

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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......

iceman2555 on Tue August 10, 2010 9:32 PM

Depends upon the type switch...is it a high pressure cut out...or is it set for the low side as protection. If memory serves me correctly, one switch is normally closed and one is normally open. The switch is normally a high side protection device, and in this case should be installed on the discharge side of the system.
Please supply the part number for your switch so that it can be validated to insure that the correct part number was supplied.

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The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

GM Tech on Tue August 10, 2010 10:45 PM

A 95 H car has an HD-6 compressor- definitely a high pressure cut-out switch-- no other switches were used in that model year compressor- mounted on the compressor....guaranteed--

-------------------------
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......

TRB on Tue August 10, 2010 10:55 PM

Is not only one side machined out (internal port) anyway?

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

iceman2555 on Tue August 10, 2010 11:34 PM

Some units have both ports machined. A metal cup is used to seal the non utilized port. GM uses two rear heads.....major difference is the 'clocking' of the manifold connection points.
I'll pull a 'head' tomorrow and check ...just to be sure.

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The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

77shovelhead on Tue August 10, 2010 11:38 PM

Man this internet thing sure makes a man lazy. Thanks for the replies. I remember back when I used to have to remember how stuff came apart in order to get it back together. Now that I think about it, I will know for sure tomorrow when I set the compressor in place and see how the wires are routed. Discharge side was my guess.

I have another issue will start another thread.




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Quality is never an accident it is always the result of intelligent effort.

TRB on Wed August 11, 2010 11:20 AM

Quote
Originally posted by: iceman2555
Some units have both ports machined. A metal cup is used to seal the non utilized port. GM uses two rear heads.....major difference is the 'clocking' of the manifold connection points.

I'll pull a 'head' tomorrow and check ...just to be sure.

For some reason I thought they only machined one side depending on the model of the head. Could be mistaken on that as I would think for production purposes it would be cheaper to machine both and use the plug as stated.

-------------------------
When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

iceman2555 on Wed August 11, 2010 1:32 PM

This is a GM 'A' read head with both switch ports machined. It is more cost efficient to machine for both and then simply use a 'plug' for the non used location. Both ports are located in the discharge side of the unit. The 'B' head is basically the same.



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The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson



Edited: Wed August 11, 2010 at 1:34 PM by iceman2555