Thank you for the guidance. I talked with the shop and they said, by law, they must pull the coolant from the system if they find leaks. The gas inside is nitrogen so I vented it via the schrader valve. I then pulled the orifice tube and uploaded a picture to the board. Link is below

It's brown in color but there are no particles on the screen. I did not get any debris when pulling apart the joint. Do I need to flush the entire system or not? If so, I've seen some of these DIY kits with pressurize bottles that allow you to squirt the A/C flush into the system components. Is that the way to go or should I have it professionally done?

A fellow board member offered me a brand new compressor that matches the installed one. He got it a few years back from a dealer that was going out of business, but has not got around to doing the swap. Are compressors ok after a few years of inactivity or should I just get a new one from FCP with a lifetime warranty?

What grade of PAG oil goes into the system? 100? 150? I cannot find specifications anywhere, even in the 240 green manual. And do I add this to the system before I take it to the shop for evac/recharge?

Thanks again for all the great information!

Quick update and a few questions...

I attempted to inspect the orifice tube, but when I began disassembling the coupling it began to spray liquid. I quickly closed it back up.

I did not expect anything to be in the system to be under pressure since it has a number of reported leaks. Obviously that is incorrect.

The stuff that came out had a slight brown color and bubbled. The small amount that fell on the concrete did NOT evaporate seems to have a slight oil consistency to it.

What should I do next? Is that stuff in the system freon? Is there a safe way to depressurize the system? How should I capture the contents?

Thanks again for all the help.

Thank you for the great advice. And I apologize for not being more clear about the compressor. 'Shot' was my term.

The shop told me that nitrogen was used to check for leaks. I don't think my system has any coolant because of the leaks, so I assume they just pressurized it with nitrogen and monitored for leaks. They said the compressor has multiple leak points and the bearings are failing. I can vouch for the bearings as the compressor makes horrible noises from tine to time. It looks like the original one (Volvo blue sticker).

I have no reason to believe there has been any internal failure that would have caused metal pieces to contaminate the lines. However, I will check when dismantling the system.

I ran an electrical test to verify the relays and wiring are working correctly. With the engine running and the A/C switch turned 'on', I did the following:

1. I disconnected the connector to the pressure switch below the headlight and bridged the connection. The electric fan ran well telling me the relays are working just fine.

2. I disconnected the connector at the drier and bridged the connection quickly. The compressor clutch engaged telling me that the circuit through computer to the compressor is working as well. I only did this briefly as I did not want to run the compressor not knowing if there is any oil in the system.

Next I'll remove and inspect the orifice tube looking for debris. Sounds like that will tell me how much cleaning I have ahead of me. I also need to find out how many pounds of coolant is needed. Not sure where to look.

I would rather buy a new compressor than try to rebuild the current one. I plan to have this vehicle for a while and would just feel better using new, quality parts.

Once I finish that inspection next week, I'll be back with a final plan and more questions.

Thank you again!

krenekj,

I had planned to do the same on our 93 245, but the truth is hot weather is so rare here that it just isn't worth it. I have the correct Volvo-Seiko compressor NOS if you're interested. Please message me off-list. In either case, report back on how it goes!

Best,
joe b.
portland, or

Hello,

Please check your orifice tube first. If its full of black oil and crud then you have to flush the entire system before installing new components.

When an ac compressor fails it blew pieces of metal particles into the system. These particles go through the condenser before they got stuck to the orifice tube. Compressor fails due to lack of oil. The refrigerant oil is lost (along with R134a) through leaking old O rings, hole in condenser or evaporator.

If your condenser is the tube-fin type then flushing can be done to remove bits and pieces of metal. If its the serpentine type then its better to replace with new. Flushing serpentine condenser is not effective to completely remove these particles.

You may have to replace the accumulator too if it has not been replaced. Accumulator contains drying material to absorb remaining moisture from the system. Much of initial moisture was already removed during vacuum pumping when the system first installed. Un-removed moisture can later be absorbed by refrigerant oil (PAG) converting it into a weak acid eating away the insides of condenser and evaporator.

By opening any part of the system you're letting outside air with moisture in (even for checking orifice tube as above). Have a vacuum pump ready beside you. Plug all opened pipe or hose while you're working. The refrigerant oil (PAG) is known to absorb moisture slowly on its own. Keep the accumulator's own fitting plugged until you're ready to install it. Install it last (after filling it with refrigerant oil). Vacuum down the system for 1hr. Then you can bring the car to ac shop to charge in the refrigerant.

To answer your questions:

1. The Omega compressor should be similar in size, appearance and its fittings to your old one. Different compressor have different pumping capacity. Your cooling performance could be affected if the new compressor have lower pumping capacity than the old one. FCP parts are ok.

Your compressor may be shipped filled with refrigerant oil. In this case you can install it straight away. If your new compressor comes without oil then you have to add it prior to installation. Please refer to its manual. On some compressor oil is added thru the suction port. On some others it is added thru a fill plug. Refrigerant oil comes with three different viscosities - PAG45, PAG100 and PAG150. Please refer the compressor manual for correct oil viscosity.

Refrigerant oil balancing (i.e how much total oil in the system) is another wide topic which depends much on compressor model and car manufacturer. Please check total oil amount specified for your Volvo model. Generally speaking put half of it into the compressor and another half into accumulator. The oil will redistribute itself when the system is running.

2. Tightening should be more than snug but not over tighten. After adding refrigerant you could test leaks at the fittings by using soapy water. Tighten a bit more if it leaks.

3. Its better to replace it also. Its no fun dismantling the compressor again just to change the bushing in the future. The bushing is crucial for proper belt alignment. Improper alignment could lead to premature belt wear or noise.

4.Yes, clean all fittings at hoses and pipes when dismantling them. Its to ensure proper seating and sealing of the O rings. O ring lubrication best done using Nylog. Mineral oil is also acceptable. No need to use Teflon tapes to seal the fittings. By design the O rings are good enough for the purpose.

Hope this helps.

Amarin.

I converted a R-12 to 134a in my 1992 245 by replacing the receiver/dryer, most of the seals (the ones that I could easily reach), and changing the orifice tube. I was able to blow out the debris with compressed air. Most of the fittings were torqued "wrench tight". I drained the old oil from the compressor the best I could. I bought a small vacuum pump at Harbor Frieght, pulled a vacuum for several hours, and charged with 3 cans of 134a and the Volvo oil. The car was still blowing cold when I finally took it off the road 4 years later.

Maybe not the absolute "correct" way, but it worked. And it cost me about $200 total to do the conversion. The vacuum pump has been used to recharge AC on 5 other cars and has paid for itself many times over.

Andy R.

You have the right idea about keeping things clean or making them cleaner if needed.

That said, my first concern is what they said about the compressor being SHOT!

Shot is a wide open term that means several things.
Shot in my terms means its very noisy or locked up.
A leaky compressor can be fixed and bearings replaced but a mechanical broken is another story, especially, if it was in use.

Not turning or pumping goes down many roads from a bad clutch, to no gas, gas with moisture and so on.

In most cases having bad valves is one thing but broken valves or other parts will require a good inspection looking for metal particles in the system. In most cases, if metallic particles are found, a flushing of the condenser in the minimum needed cleaning.
With them recommending a changing out the orifice tube, its a precaution, if later it is found out that compressor had disintegrated. This will have plugged the orifice and would have cause excess head pressure and probably have blown out the refrigerant through the pressure relief safety valve. In the mean time the compressor should have locked up or sounded really bad.
Did any of that happen?


If you are removing these components you need to be aware of this possibility. If you fail to take this fact into the repair it will void all warranties especially from your "good shop."
Did they share this with you so you would not walk into it later?

If not, the tube may be fine and a flow check through it will define if it needs to be changed out. No need for the effort or expense.

They may have done that with inert gas or refrigerant from a bottle during their "diagnosis." If they had a non-working compressor it's the only way! Knowing how things work can create good questions to see what was done or not and it works for both parties!

If they say it was plugged plan on seeing metal flakes plus doing a flush of both the evaporator and condenser while changing the tube out. You will need some solvent and a way to blow it through the system into clean rags until clear.

Inert gas is best, as it is a dry gas. If you have to use compressed air then you may induce moisture. Not a big deal but something that you will have to remove with a new desiccant package (the dryer you mentioned) and a very good vacuuming job with purges and leak checks.

All of the latter will be on them and is the easiest part of the whole job, lucky them!

I Hope you are not only saving some bucks but depositing the knowledge in the great bank upstairs! It was a similar experience years ago put me on a trail of later working in the trade of HVAC.

You have the right idea as I mentioned earlier. Moisture is the smallest enemy but is the major one you do not want in the system. As far as dirt and stuff, taping will work. Just use caution when moving things about as it helps even better.
Tape will never hurt but be sure to remove any residue from mating surfaces where seals fit.

Clean smooth surfaces with out distortion (crooked alignment) when bolting is very important. Keep strain from being applied to any tubing.

Torque on bolts can be referenced to their size. The seal does the job. You want to stretch the bolt just enough to remove clearances in the threads so it will not vibrate loose.

Keep the gorilla in the back pocket for those big rusty things!

Good luck with this endeavor!
Phil