Author Topic: Air condioner compressor question  (Read 3830 times)

Offline gunrac

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Air condioner compressor question
« on: April 15, 2017, 10:11:04 AM »
Working on coolin down the 94'.....I definitely need a new compressor. Debating on new or reman. Couple yr. ago I tried getting it to go. Ended up putting in new O-Rings, Gaskets, Accumulator and oil.  When adding Refrigerant, I had difficulty with compressor. It would keep trying but just kept kicking on and off, fairly quickly. A fella suggested I jump wire it. Never did get it going.
Now I'm down here in TX., I'm bound and determined to make it go.  I did kick it on a while back. Clutch was chattering. So I'm leading toward replacement. Any tip's? Will I need to add oil? Should  I just take it somewhere to set up, after install?
This truck set for five years before I started driving it.
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Offline bd

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Re: Air condioner compressor question
« Reply #1 on: April 15, 2017, 10:22:36 AM »
Did you evacuate it before recharging?  What were the high and low side pressures?
Rich
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In other words... if people learn by making mistakes, by now I should know just about everything!!!
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Offline gunrac

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Re: Air condioner compressor question
« Reply #2 on: April 15, 2017, 10:29:40 AM »
After replacement of O-Rings, Gaskets, Accumulator and oil, guess I never thought of releasing any air that might be trapped. Can you explain how to do this?
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Offline bd

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Re: Air condioner compressor question
« Reply #3 on: April 15, 2017, 11:40:08 AM »
You need an A/C vacuum pump and proper set of gauges.  How much oil did you add? 
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline hatzie

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Re: Air condioner compressor question
« Reply #4 on: April 15, 2017, 11:43:19 AM »
AC is a bit more involved than throwing on some parts and filling with oil and refrigerant.  You need a decent vacuum pump and manifold gauges at a minimum.

If you overfill the system with oil it'll impede thermal transfer by insulating the inside of the evaporator and condenser.  It can also hydraulically lock the compressor.  It's a very common mistake.
Overcharging with refrigerant is the second most common mistake.

The 73-78 GM service manuals have a fair amount of theory of operation information and service info about GM AC service.

A bit of "light" reading from GM Service Training on AC service... http://www.mediafire.com/file/11dxhweexlqg54v/GM_STG_11004_00_2_FUNDAMENTALS_OF_AIR_CONDITIONING.pdf
The 1994 GM T400 CK service manuals are here.  https://www.mediafire.com/folder/2rib17e2fiuee/1994
« Last Edit: April 15, 2017, 11:47:09 AM by hatzie »
SVC & wiring mans --> Here http://tinyurl.com/7387BRD-SVCMAN or My Bucket @ http://tinyurl.com/SQ-SVCMAN
Parts & Illustr Books -->http://tinyurl.com/SqParts
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Offline gunrac

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Re: Air condioner compressor question
« Reply #5 on: April 15, 2017, 11:47:52 AM »
K......I got it. I swap out parts and let someone w/the proper equip. juice it up.....THX for the heads up.
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Offline bd

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Re: Air condioner compressor question
« Reply #6 on: April 15, 2017, 01:17:48 PM »
At this juncture you should plan for a complete system flush (excluding the compressor) a new orifice tube, another new accumulator and an appropriate amount of the correct refrigerant oil, followed by immediate evacuation and recharge.  I think it's in your best interest to leave the balance of the work to a professional.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline gunrac

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Re: Air condioner compressor question
« Reply #7 on: April 15, 2017, 04:11:24 PM »
After a fella backed into the truck, I will need a new condenser also.
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Offline bd

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Re: Air condioner compressor question
« Reply #8 on: April 15, 2017, 04:29:22 PM »
Don't tell us that happened today!?!!
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline zieg85

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Re: Air condioner compressor question
« Reply #9 on: April 15, 2017, 04:34:26 PM »
After a fella backed into the truck, I will need a new condenser also.
Assuming the guy has insurance, get the insurance company to fix it and recharge the system because it was working perfectly before he backed into it ;)
Carl 
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Offline gunrac

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Re: Air condioner compressor question
« Reply #10 on: April 16, 2017, 08:39:39 AM »
Don't tell us that happened today!?!!

After a fella backed into the truck, I will need a new condenser also.
Assuming the guy has insurance, get the insurance company to fix it and recharge the system because it was working perfectly before he backed into it ;)

LOL.....No it happened about 3 wks. ago......they just cut me a check. I did ok. Plenty to take care of damages including AC.
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Offline Irish_Alley

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Re: Air condioner compressor question
« Reply #11 on: April 22, 2017, 09:46:32 AM »
a few years ago i had to replace my ac system in my 94 c1500. the wife a few years before had wrecked it, and the condenser was off an older truck with r4 so the hoses didnt match. i ended up doing some research with a parts catalog and finding out what condenser i needed took that part number to autozone and order through them.

ended up replacing the condenser, compressor, accumulator and orifice tube. the 94 requires R134A PAG 150   2lbs of 134A.

since my system wasnt connected i ended up connecting the hoses wrong to the condenser and caused the system to try and go the wrong way past the orifice tube. causing the compressor to cycle on and off constantly.

i got a can of ac flush from the parts store and flushed the system, it will get messy.

you can rent a vacuum pump from the parts store. i forget how long i pumped mine but it was a few hours, once you get water to a certain vacuum it will boil and the pump will discharge of it, if left in the system the chemical reaction between water (moisture in the air) and freon will eat away at the system

http://www.aircondition.com/tech/questions/38/
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