I have replaced the radiator and now I want to replace the condenser. I have read some of the threads about chemicals to clean it up and I will try that first but they don't seem to expensive so I was hoping for some help on changing it. I would have my garage evacuate the old coolant and after that it seems pretty straight forward. Do I just swap it out and recharge or am I being totally ignorant here. Do I need to do anything to the compressor or drier/accumulator. Bleed the system or oil anything. The condenser is totally packed in with crap, dirt and bugs. I don't mind the work or the money I just want to beware of hidden things I should do. The a/c does work okay as is, I guess I am a glutton for spending time and money on my quest for a cool car. Any help would be appreciated. Thanks and have a great holiday everyone. I wish it would stop snowing here in New England so I could get in one last rip.

 

Eric:

I just completed totally rebuilding my 86 A/C system and in the process I installed a new front condenser. Once the system is evacuated, there is not much to replacing the condenser. Just unbolt the upper bolts on the main fan assembly, remove the radiator shroud bolts and shroud, disconnect the A/C lines to the condenser and then lift out the old condenser. There will be alot of leaves and trash between the radiator and the condenser. Vacuum and clean all of this stuff out - thoroughly.

You should add about one oz. of oil to the condenser before you reinstall it. By looking at your engine photos, it looks like you have converted your sytem to R134A refrigerant. I think this because your accumulator is not stock and has a green Schrader valve cover. If you have kept your system R12, you will need to add one oz of mineral oil to the condenser. If you have converted to R134A, you will need to add Ester oil. You can not mix these oils so don't get it wrong here.

The reassembly is pretty simple, just sit the condenser in place, replace the top and bottom rubber bumpers, shroud, A/C lines and fan bolts and you are finished. My condenser replacement took me about 2 hours, but I work slow and took about an hour to vacuum and thoroughly clean out the old trash and vacuum the front of the radiator fins.

My rebuilt system works well and the car runs about 15 degrees cooler now.

 

Once you open it up or expose the system to air, the Accumulator is shot - so replace it too.

Oil capacity is 8 ozs. Most of that is usually in the Accumulator so whatever you can drain out of it, add it back. Then, as suggested, put an ounce in the new Condensor.

You'll need to pull a vacuum before you recharge to get the air/moisture out. Might not be a bad idea to have the system leak checked before you tear it apart. A shop can go over it in 15 minutes or less with an electronic leak detector and shouldn't charge more than a couple of bucks to do it.

 

Thanks for the info, seems fairly easy and it just seems a new condenser is the way to go, I already replaced the radiator and cleaned out all the garbage, I was just unsure of what oil to add and where. Yes, it is r134. Thanks again-E

 

Is the accumulator the metal canister where you charge the system. Some people call it a drier I think. Couple questions. Where do you put the oil into the accumulator and what kind of oil. also, How do you pull a vacuum check. I am a bit inexperienced and have so far just dealt with nuts and bolts. If it is really complicated you don't have to take the time to explain. I appreciate what you have told me so far. Thanks again.-E

 

Accumulator/Drier means the same thing. It actually does a bit of both - accumulates any liquid that wasn't boiled off in the Evaporator and absorbs any moisture that may have been in the system. If either reaches the compressor it will destroy it.

It doesn't matter whether the oil is added in the Inlet (from the Evaporator) or Outlet (to the Compressor); just add whatever you drain out of the old one.

If your Vette is converted to R134, use Ester. If it's still R12, use Mineral Oil.

Evacuation of air/moisture is with a vacuum pump. You can get by with a 9 Buck displacement pump (Harbor Freight) that uses a compressor (5 hp or better) or spend a few more Bucks on the real deal. You connect either to the Center or Charge hose of a Manifold Gage Set. The Low or Blue hose from the Gage set goes to the Low Side fitting on the Accumulator. The High or Red Hose goes to the high fitting on the line (smaller) running from the Condensor to the Evaporator. Crank up the pump and open both valves on the Gage set. Monitor the Low Side gage to read the vacuum. You want about 28 inches at Sea Level. A tight system will reach this in a couple of minutes, but you'll need to run the pump for a bit longer - I like at least an hour. After that, close the gage valves and turn off the pump. The vacuum should hold or drop a point as any remaining moisture is vaporized. Run the pump again until the vacuum reading holds - or if it doesn't hold, there's a leak and you'll need to find it. Assuming it's steady, disconnect the pump and hookup a can of gas to the Charge hose. Open the Low Valve (ONLY!) and allow the vacuum to suck in that can. Close the Valve and start the motor. Disconnect the fan switch on the high pressure line to keep the Main Radiator Fan running. Block the throttle so it's at 1200 to 1500 rpms and with the a/c on max, add another can. R12 capacity is 2.25 lbs or 36 ozs or three 12 oz cans. With R134, it's smaller molecule demands less - use maybe 80% of the R12 fill or charge until the high side pressure is 2.2 to 2.5 times the temp of the air flowing through the Condensor (about 10 degrees above ambient for a bottom feeder like the Vette).