I need compressor help!
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,853
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
All 1979 cars used the standard R4 (radial) compressor. (Short one).
If you are missing the compressor, you should replace the drier on the car, the orifice for sure! The odds are not in your favor the last compressor did not lock up and thus the PO's removal. If the metal from the old compressor is still in the system it will eat up the new compressor!
Normally when a compressor tanks, the metal will end up in the drier and the orifice! It’s important to get this out!
Not knowing what happened before would almost make me want to flush the entire system! I hate AC work, and the only thing I hate worse is AC not working! You don’t want to do this job twice so you have to be smart!
Willcox Inc.
If you are missing the compressor, you should replace the drier on the car, the orifice for sure! The odds are not in your favor the last compressor did not lock up and thus the PO's removal. If the metal from the old compressor is still in the system it will eat up the new compressor!
Normally when a compressor tanks, the metal will end up in the drier and the orifice! It’s important to get this out!
Not knowing what happened before would almost make me want to flush the entire system! I hate AC work, and the only thing I hate worse is AC not working! You don’t want to do this job twice so you have to be smart!
Willcox Inc.
Burning Brakes
Joined: Jun 2008
Posts: 1,086
Likes: 1
From: Michigan
If you replace the compressor be sure to replace the dryer and oriface tube as a minimum. Also flush the system with A/C flush you can buy in a pressurized can or use an air compressor to force it through the system.
Be sure to add PAG oil to the compressor and turn it over a few times by hand or you will burn it out. Add the rest of the PAG oil to the system until you have the correct amount. If you aren't using R134a, this is the time to do the conversion with a conversion kit.
When adding new refrigerant you have to evaculate the system with a vacuum pump for at least 1/2 hour to get out all the air and moisture. You can rent a pump free from Autozone.
http://www.corvettemagazine.com/comp...iendly-ac.html
http://www.ackits.com/merchant.mvc?S...t79corvette5-7
http://www.corvettesouth.com/corvett...0/index-2.html
Be sure to add PAG oil to the compressor and turn it over a few times by hand or you will burn it out. Add the rest of the PAG oil to the system until you have the correct amount. If you aren't using R134a, this is the time to do the conversion with a conversion kit.
When adding new refrigerant you have to evaculate the system with a vacuum pump for at least 1/2 hour to get out all the air and moisture. You can rent a pump free from Autozone.
http://www.corvettemagazine.com/comp...iendly-ac.html
http://www.ackits.com/merchant.mvc?S...t79corvette5-7
http://www.corvettesouth.com/corvett...0/index-2.html
Racer
Joined: Dec 2007
Posts: 445
Likes: 2
From: Thomastown Mississippi
If the drier is in the same location as on my '77, you need to remove the plastic coolant recovery tank. Once you do that, you should be able to lift the drier up enough to get a wrench on the nuts holding the hoses on. The drier isn't bolted to the car, it's just attached to the hoses. Also, there should be a thermostat with two wires coming off of it, attached to a bracket next to the drier. Be sure it's there, and is wired correctly. One wire should be going to the compressor, and the other to the low pressure switch. This thermostat is what makes your compressor cycle on and off, and keeps it from freezing up, and burning up. There should also be a sensor coming from the thermostat, and attaching to the metal line that the orifice tube is in. It'll probably be wraped in some sort of insulation. Just be sure all this stuff is in place. If you look down, just to the right of the drier, you should be able to see the thermostat. You can get replacement thermostats at any parts house. I just redid the a/c on my 77, so if you have any questions, I'll try to help. Good luck. It's a messy job, but it's worth it to have the a/c working. Mine won't freeze you out in the heat of the day, but it sure makes it comfortable in the mornings and evenings.
Racer
Joined: Dec 2006
Posts: 281
Likes: 0
From: Nashville Tennessee
St. Jude Donor '10
My drier/accumulator is attached, with a "wrap-around" type bracket, to a bracket on the evaporator box. (one bolt) One of the lines going into the drier/accumulator is attached to this bracket as well.
By going in from the bottom, I found I had plenty of room for the large tools you need to break the nuts on the compressor lines free. (penetrating oil is your friend here).
Just my $.02...I would consider replacing your compressor hoses,(rubber w/metal ends) while you're in there. (both lines are hooked together as a unit where they go into your compressor) They are 30+ years old...and in most cases...a leak waiting to happen. And they aren't really that expensive.
Good luck with it,
Bobby
Burning Brakes
Joined: Jun 2008
Posts: 1,086
Likes: 1
From: Michigan
C3BDJ1 is right about getting at the dryer from underneith. To get the panel out you will have to remove the two front screws that hold the rocker molding on to get at the last two screws that hold the panel on.
It is also imparitive to flush the system before installing the new components and to evacuate the system to as close as you can get to one atmosphere or about 25-28" Hg for at least 1/2 hour, before putting in the new refrigerant. You can rent a vacuum pump for this purpose and other A/C tools free of charge from Autozone. You can also get the flush stuff with a hose attachment on a pressurized can from any auto parts store as well. Or you can buy a can of flush and use your air compressor to blow it through the system. Put a hose in a coffee can with a star slit in the top of the can to catch the flush. You don't want it all over your engine bay or your paint.
It is also imparitive to flush the system before installing the new components and to evacuate the system to as close as you can get to one atmosphere or about 25-28" Hg for at least 1/2 hour, before putting in the new refrigerant. You can rent a vacuum pump for this purpose and other A/C tools free of charge from Autozone. You can also get the flush stuff with a hose attachment on a pressurized can from any auto parts store as well. Or you can buy a can of flush and use your air compressor to blow it through the system. Put a hose in a coffee can with a star slit in the top of the can to catch the flush. You don't want it all over your engine bay or your paint.
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