Just replaced the compressor on my 1983 F-150. The old one was working, but had a badly damaged nosepiece that the clutch rides on. You had to see it. Anyway, we pulled a good vacuum, let it sit for an hour and a half, rechecked the vacuum, which was still just fine, and started refilling the system.

Its been running witn R134 for about 6 years now. I added one can of oil for the used replacement compressor. My friend, who was helping, added 3 cans of R134/oil without telling me. The system only holds so much. The system is cold, but not as cold as before. Pressures are close to normal. I cant get anymore R134 into the system. I'm not a newbie with a/c. Been doing this since 1970.

I think there is too much oil in the system. Do I need to evacuate the system again? How to get the oil out? I've never had this problem before.

The replacement compressor is used, but was tested by a friend at my local Ferd dealer. It came from a low-mileage Lincoln that got totaled... hit in the rearend.

I appreciate any and all comments. I just dont want to waste alot of money on R134 again. My reclaimer does not like R134...

 

My 99 F-350 uses a maximum of about 12 ounces for a complete replacement of all the oil. If I understand you correctly 4 cans of refrigerant oil has been added to what already was in the system. If each can is 16 ozs that's 64 oz of refrigerant oil or over 5 times what is needed. I would discharge the system and open up the system at the condensor and using lacquer thinner or some other recommended cleaner and air pressure clean out all of the oil there. Same at the evaporator, accumulator and compressor. You might have to replace the accumulator since you may not be able to get enough out of there using lacquer thinner and air pressure. If you get all the oil out or at least most of it then I would add 4 ozs for the compressor, 2 ozs for accumulator, 2 for the evaporator and 2 for the condensor. Assuming there will be some residual left this should put you about where you want to be. Pull a vacuum and then recharge.

John

 

(Dirty word here.)

I dread this job. Been a long time since I've done it.

Thanks for the fast response!

 

I disconnected the condenser after I discharged the system. I flushed it out with laquer thinner several times until the stuff coming out was clear. Blew it out with compressed air.

Using new O rings on everything, reassembled, charged it with no additional oil. It's getting much cooler and feels like it did before the compressor replacement.

I was dreading pulling any of it apart, but it was less trouble than anticipated. 20+ year old parts seem to break at the worst possible time! Nothing unusual happened.

 

Good news that you didn't have to flush everything. Sounds like you have the situation in control. What is your center discharge temp down to and what pressures are you seeing?

John

 

Never flush the compressor, accumulator or hose that has a inline muffler built on to it. Anytime the A/C sytem is opened up you should replace the accumulator and oriface tube.

 

So far, so good. Ran the A/C during a 200 mile run yesterday. Other half kept inching the temperature lever toward warm. I think that it will be OK.

My other half is a good indicator. According to the gauge inserted into the center vent, the air coming out averaged 42 degrees. The compressor runs quiet. I've never installed a used compressor before. I'm satisfied, for now.