New AC Compressor - Add oil to it?

[turbojimmy]

I converted my AC system to 134a a few years ago (actually many years ago). Every year the refrigerant leaks out to the point where the compressor won't run anymore, but there is still pressure in the system. I just top it off and it works decent.

This year, the compressor won't run even when jumped. It was a "new" Four Seizens compressor at the time, and has always sounded like a box of rocks. I broke down and got a new GM compressor today.

I plan to open up the system, install the compressor, and vacuum it back down. The question is: do I need to ad Ester oil to the new compressor? If so, how much? Obviously there is already oil in the system.

Thanks,
Jim

 

[garyk1970]

yes....pour a ounce or two strait into the new compressor,then spin the compressor/clutch by hand before you bolt it up to the car....

edit....check the orifice tube for metal(s)....if any flush the system and replace the accumulator....

 

[X Ray]

Instructions

Yes you do ...the instruction are taped on the compressor...

 

[turbojimmy]

Yes you do ...the instruction are taped on the compressor...

Thanks both. Haven't seen the compressor yet - my brother picked it up for me. Just thought I'd be proactive and ask.....

EDIT: I'll check the orifice tube for metal. The old compressor sounded awful.

Jim

 

[turbojimmy]

So the orifice tube has lots of metal in it. Now what? Do I have to remove the condenser and evaporator core to clean it out? Or have a professional flush it?

EDIT: Also, what replacement orifice tube do I get. I remember something being special about the one I have in it. Some sort of special deal for conversions.

Thanks,
Jim

 

[turbojimmy]

Post Mortem

Thanks to X Ray for the tips.

The compressor I got from GM was a Delco "service compressor". It's a slightly different design that requires a washer kit in order to work with our Buicks. On the compressor, the suction and discharge ports are offset. Our line block is flat. The compressor electrical fitting is also in the 4-5 o'clock position rather than the 2-o'clock position on our stock compressors. It's actually a better spot because the bracket isn't in the way.

The compressor came with GM Seal Washer Kit #2724887. The kit comes with the following items:

Yellow sealing washer
Red sealing washer
Green Sealing washer
Long insert
Short insert

According to the instructions, our application uses the following:
Black washer on the suction portion of the line block (did you see a black washer listed above? Of course not....more on that in a minute)
Green washer and short insert on the discharge side

Now it looked like maybe the yellow washer would work on the suction port, but I'm anal about these things and ordered Seal Washer Kit #2724575 which comes with two black washers. So I had all the right parts to put the compressor together.

I used a flushing solvent that I bought at Autozone to flush the condenser, evaporator and the lines. Replaced the accumulator. If you let the dealer look up the accumulator they will give you the wrong one. Use the part number on the GNTTYPE site to make sure you get the right one. My GM parts guy says that the number on GNTTYPE cross references only to trucks. But it is correct for our cars.

The instructions that came with the compressor tell you how much oil to add for each component you're replacing. Since I flushed all of the oil out of it, I added enough oil as if I had replaced the condenser and evaporator core in addition to the compressor and accumulator.

Sucked it down to 30 in/hg for about half an hour and charged it up. The new compressor is so quiet I had to go around and look at it to make sure the clutch had engaged and that it was spinning. That stupid Four Seizens sounded like a box of rocks from the second I fired it up.

Outlet temps are down to 45 degrees, which is not bad. It's nice to have AC again.

Oh, if you have FAST and your compressor isn't running check the coolant temp cutout settings before you start pulling your hair out and checking relays and such. Ask me how I know.

Jim

 

[TURBOTWIN2]

Oh, if you have FAST and your compressor isn't running check the coolant temp cutout settings before you start pulling your hair out and checking relays and such. Ask me how I know.
Jim

How do you know?

Couldn't resist.:biggrin:

 

[turbojimmy]

How do you know?

Couldn't resist.:biggrin:

I know because I spent half the day beating my head against the wall. I had forgotten that I had borrowed a configuration file last fall that didn't have the AC parameters set. The compressor was set to shut off at 11 degrees, which is pretty much always off. I bumped it up to 200. Should be adequate.

Glad I got it sorted out though. It hasn't worked right in many years. A/C is a luxury that I had taken for granted. The pressures are still a little low but the outlet temp stopped dropping with the last can so I guess it's charged.

Jim

 

[gsgns4me]

So the orifice tube has lots of metal in it. Now what? Do I have to remove the condenser and evaporator core to clean it out? Or have a professional flush it?

EDIT: Also, what replacement orifice tube do I get. I remember something being special about the one I have in it. Some sort of special deal for conversions.

Thanks,
Jim

So which orifice tube did you use?

 

[DailyDrifter]

Metal in the orafice tube :frown: . You could try cleaning the lines out, and maybe replace the reciever/dryer. But there could still be metal floating around in the condensor and evaporator that could possibly wipe out the new compressor. I dont think even the professional machines will clean the metal out of it (at least not the one at my work).

 

[turbojimmy]

Metal in the orafice tube :frown: . You could try cleaning the lines out, and maybe replace the reciever/dryer. But there could still be metal floating around in the condensor and evaporator that could possibly wipe out the new compressor. I dont think even the professional machines will clean the metal out of it (at least not the one at my work).

I flushed everything and hoped for the best. I ran around all day yesterday with the a/c running and the compressor hasn't started making noise yet. I had an appointment to have a shop do it, and they told me that they can't guarantee to get all the metal out. But then my TA broke down and I canceled that appointment anyway. Then I figured I'd just take a crack at it myself with that Autozone stuff. So far so good.

I used the orifice tube that GM gave me.

Jim

 

[Roger]

'87 Buick service manual: Regal & GN require 6 ounces of 525 viscosity refrigerant oil.
I'm told the ester oil is a suitable replacement & the 525 is no longer available.

 

[87GN_70GS]

I got the same service replacement compressor and the sticker attached to it said it had no oil in it and to add oil. But as I was peering into the suction/disch ports looking for oil, some very thick clear goo (oil) came out. Must've been super high viscosity stuff. I added oil anyway like the instructions said and so far, so good. I used the sealing washers that came with the comp.