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R-12 auto A/C tech in chit chat

Rttoys said:
  1. Replace the o-rings and keep it R-12. But if leaks persist I will run out of R-12. Is there R-12 leak dye any more?
  2. R-134a conversion. But what about the R-12 lube and the fact that R-12 system pressures are not right for R-134a? What other stuff would I need to do?
  3. Bacon.
1. I have the o rings sitting in my toolbox. There’s a ton of adaptor o rings depending on exactly what updated compressor you have (there were several updates). A pic of the line separated from the comp so I/we can see what else are dealing with would be best. A lot of the adaptor o rings/seal never worked exactly right, but worked.
2. I would do the conversion though. I was at the dealer when this all came about, so I’m familiar with it. The 2 oils are but are not compatible. Basically, GM recommended replacing the accumulator (trying to remember if the orfice needed replacement too, I don’t think so though) and flushing out as much oil as possible. You can flush the lines with denatured alcohol and compressed air. If you feel frogs, pull the compressor and try to dump any oil that’s in there too. Then you add in the r134a oil. There was a big mathematical equation GM had for the conversion for the amount of Freon needed. Basically, it was .5# less :homer:
3. mmmmmmmmmbacon. Aaaaahhhhhh
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Pictures attached of the compressor and manifold. Also of the orings that were in there - there was one marked green and on the other side two were stacked. Does not seem right. I know there had been problems finding the right ones to marry the stock manifold to the new compressor.

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that shit's fucking nasty
you're gonna be throwing a lot of money at this pile to get the AC going long-term

plus side is you don't gotta worry about converting it to 134, as you're gonna be replacing everything anyways
 
[486] said:
that shit's fucking nasty
you're gonna be throwing a lot of money at this pile to get the AC going long-term

plus side is you don't gotta worry about converting it to 134, as you're gonna be replacing everything anyways
Click to expand...
Yeah, it's pretty crusty. What o rings do I need to mate A to B?

So I can either clean the shit up as best I can, replace the manifold to compressor orings/seals with the correct ones, pump it down, top off with the R12 I still have left, and look for smoke.

OR, I could say fuck it and get something like this:

346003 - 1988-93 GM Truck Sanden AC System Upgrade - Small Block V8 - W/O Evaporator
 
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plym49.2 said:
Yeah, it's pretty crusty. What o rings do I need to mate A to B?
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they're those bonded rubber type seals, but you only run one on each
get a new line too while you're at it, that crusty shit's gotta go
 
M92PV4U said:
Do you already have the new compressor? I believe that it comes with instructions on which to use.
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That compressor is new. Buddy of mine swapped it out for me at his shop because he owed me a favor. He said they had trouble getting the correct seals. The system worked for a while, then started leaking, then blew out at the manifold-compressor connection, and Bob's yer uncle.
 
plym49.2 said:
That compressor is new. Buddy of mine swapped it out for me at his shop because he owed me a favor. He said they had trouble getting the correct seals. The system worked for a while, then started leaking, then blew out at the manifold-compressor connection, and Bob's yer uncle.
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I believe that I have the instructions on what to use at work but it's not going to last long with that corrosion flaking off.
 
M92PV4U said:
I believe that I have the instructions on what to use at work but it's not going to last long with that corrosion flaking off.
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Yeah, that's the dilemma. I can nail it together or do it right. I have a road trip that might be coming up soon that would give me a chance to wheel in southern Utah. I don't have a lot of prep time or the coin just now so maybe I can slim shady it pretty much as-is and then deal with it properly later on at my leisure.
 
hack job it and fill it with duster for trip.

repair properly and use precious r12 later.

a can cracker fits the duster cans fine.

we did this to an old tracker with an r12 system that nobody wanted to deal with and it worked fine.

A/C Charging with Easy Cheap Safe Alternative Refrigerant - RX7Club.com - Mazda RX7 Forum

1st Gen Archive - A/C Charging with Easy Cheap Safe Alternative Refrigerant - I am knowledgeable about Auto A/C (as well as Home and Refrigeration etc). I am licensed, I have a 608 and a 609 certificate. I have EPA certified recovery equipment and am capable of doing everything 'by the book'. I...
www.rx7club.com
 
87manche said:
hack job it and fill it with duster for trip.

repair properly and use precious r12 later.

a can cracker fits the duster cans fine.

we did this to an old tracker with an r12 system that nobody wanted to deal with and it worked fine.

A/C Charging with Easy Cheap Safe Alternative Refrigerant - RX7Club.com - Mazda RX7 Forum

1st Gen Archive - A/C Charging with Easy Cheap Safe Alternative Refrigerant - I am knowledgeable about Auto A/C (as well as Home and Refrigeration etc). I am licensed, I have a 608 and a 609 certificate. I have EPA certified recovery equipment and am capable of doing everything 'by the book'. I...
www.rx7club.com
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This is what I will do. If it does not work, I will be running to Utah in August with no A/C. Whatever.

Does anyone know if this kit provides a good selection of the bonded rubber seals I need to connect A to B?

Amazon.com
 
Time for an update. Went through last summer with no A/C because fuck it. In November I was up north so I got together with my buddy who got the system working a few years ago. (System subsequently bled out when a compressor oring/seal failed.)

We installed a new drier and orifice tube. Added a small amount of ester oil. Replaced compressor seals and all orings on the lines. Pumped down the system. Filled with R12.

It cooled beautifully. For a few minutes.

Then the engine slowed, the belt started chirping, the compressor locked up (clutch engaged and belt slipping). And my gauges gave up the ghost (hoses shot). Maybe oil bound?

Disgusted and out of time, I D/C'd the compressor clutch and drove back to TX.

When I got here, I reconnected the clutch and turned the A/C on. Clutch did not engage. I have not jumped it or the low pressure switch or checked for pressure in the system because I was just pissed.

Buddy bought me a new compressor and drier. Sitting here in boxes. I have also accumulated everything needed to fill it with Duster, R-12, or 134a.

I am thinking of checking out the compressor to see if it is hosed. If not, I will flush the system and (maybe) change the accumulator and top it off with Duster.

If the compressor is hosed, I am tempted to get the '94 Chebby condenser, low pressure switch, and orifice tube. Install the new compressor. Recharge with 134a.

Reactions? Maybe a better idea?
 
Could be oil bound but usually when that happens it breaks a piston ring or something like that and just gets noisey.

You should be able to turn the compressor by hand. If you can't it is locked up. Couild be bad bearings, was this one of those vehicles that suffered from black death? Where the previous dessicant bag would break open and plug the system?
 
I converted my 93 to r134a by putting the 94 condenser in. Replaced the compressor, orifice tube, and accumulator, pulled a vacuum, dropped in ACDelco PAG oil, and then refilled with the proper amount of r134a for a 1994 truck. It blew ice cold until I sold it.
 
Tiha said:
Could be oil bound but usually when that happens it breaks a piston ring or something like that and just gets noisey.

You should be able to turn the compressor by hand. If you can't it is locked up. Couild be bad bearings, was this one of those vehicles that suffered from black death? Where the previous dessicant bag would break open and plug the system?
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Now that you mention it, it did get noisy. Maybe that was some of the noise we heard?

Never heard of the black death. I'll check the compressor today.
 
I tried to spin the compressor by hand. It is crunchy and has a very hard spot. So it is toast.

I know, from the advice in this thread, that the right thing to do is to replace the condenser and orifice tube with those from a '94 model truck. I am fine doing that but the stingy bastard in me is wondering if how risky it would be to remove the compressor and accumulator, blow out the lines with brake cleaner or alcohol, clean the orifice tube, replace the compressor and accumulator (have new ones on hand), reoil with ester oil (have it on hand), and charge with duster (I have plenty and a can tap).

If this works, then I am done and if not, can swap out as listed above, clean out again and recharge with the Delco oil and R134. I have another new accumulator on hand as well.
 
Worth a try. What's the worst that can happen?
 
Mikel said:
Worth a try. What's the worst that can happen?
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Paranoid about killing the new compressor. But I guess that could happen either way depending upon how well I flush things out.
 
If you have no debris in your system from a catastrophic compressor failure, an imperfect flushing should be sufficient.
 
plym49.2 said:
I tried to spin the compressor by hand. It is crunchy and has a very hard spot. So it is toast.

I know, from the advice in this thread, that the right thing to do is to replace the condenser and orifice tube with those from a '94 model truck. I am fine doing that but the stingy bastard in me is wondering if how risky it would be to remove the compressor and accumulator, blow out the lines with brake cleaner or alcohol, clean the orifice tube, replace the compressor and accumulator (have new ones on hand), reoil with ester oil (have it on hand), and charge with duster (I have plenty and a can tap).

If this works, then I am done and if not, can swap out as listed above, clean out again and recharge with the Delco oil and R134. I have another new accumulator on hand as well.
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So you’d rather do it twice hoping it works the first time? Seems odd even for a cheap bastard. I know ester oil is cheap, but removing the stuff to do a full swap seems like the best option and cheaper because it’s less time and less shit to fuck up. Waste of money on ester oil if it doesn’t work but I guess I don’t understand that cheap life.
 
RunningProblem said:
So you’d rather do it twice hoping it works the first time? Seems odd even for a cheap bastard. I know ester oil is cheap, but removing the stuff to do a full swap seems like the best option and cheaper because it’s less time and less shit to fuck up. Waste of money on ester oil if it doesn’t work but I guess I don’t understand that cheap life.
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Yep.

Rationale is because to do it all at this time would strain time and budget. This thread is almost a year old - that should tell you something.

I am extremely grateful for the terrific information that folks have been providing. For example, the bit about using a later-model condenser and orifice tube when switching to 134.
 
I am running out of excuses to not be working on this. I found two tanks of R-12 I had stashed away. One is at least 1/3 full and the other is brand new with the seal still attached.

I think I will end up replacing the condenser because the original one inn the truck looks pretty gnarly.

Questions:

  1. If I go with the later-model condenser recommended earlier in this thread (the unit used in R-134a vehicles), will it work with R12? (If it does, then I have a hedge against a possible future 134 conversion.)

  2. Does the later-model condenser require new hard lines? It looks like the connections are in a different place.

  3. I plan on blowing the lines and evaporator out with brake clean and air pressure. Want to get all old oil and anything else blown out. What is the correct procedure for filling a new system with oil? (Will be getting a new compressor that is shipped dry.)
 
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Vacuum the system after blowing it out.

Tons of shit in the 90s spec'd the system parts sizes for 134 and then filled them from the factory with 12 until the cutoff.
 
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plym49.2 said:
I plan on blowing the lines and evaporator out with brake clean and air pressure. Want to get all old oil and anything else blown out. What is the correct procedure for filling a new system with oil? (Will be getting a new compressor that is shipped dry.)
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I believe that a/c flush is some kind of citrus solvent, but don't see how brake parts cleaner will harm anything as long as it evaporates before the system is charged, I do have the factory manual for this truck at work and can get you the oil capacities, I won't be at the shop today though.
You just add a certain amount of oil to each component.
 
the chances of getting a pancake compressor worth a shit these days is pretty slim. I'd convert it to a sanden compressor at the least. under a 100 for a 94 jeep one thats the same as the universal one everybody sells for 200.
 
Ummm, holy necro thread, Batman.

FINALLY in a position to get this A/C system working again. Yep, it's been a while.

I decided to replace everything stem to stern because 37 years old. I have been buying all of the parts and as this will end up being a bit of a hybrid install I figured I should ask y'all for some advice.

I have already installed the wider (30+ inches wide) three-row radiator as opposed to the narrow (20-odd") the truck came with. The new unit has the trans and oil coolers built in so I am good to go there.

I purchased the wider '94-up condenser as y'all recommended earlier. Since the fittings line up differently I figured that I should buy everything else '94-up as well - the lines, dryer, and evaporator.

Now the '94-up is an 134A system, right? Do they use an expansion tube? Because I do not see a listing for one and the '94-up lines do not seem to have provision for one.

This will be an R-12 system because I still have plenty of R-12, I have nothing else that would use it, and it should cool better.

Do I instead get the '88-up line as that has provision for the expansion tube? Or is this part not needed for whatever reason?

Also, will the o-rings that came with these new parts work with the r-12 compatible oil?

TIA.
 
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