Replacing a '93 a/c system with '96 parts

[scrivyscriv]

Can I do that?

I bought the Ex with 98,000 and R12, running cold, and it ran cold for a month, slowly blowing warmer until finally nothing. I converted to 134 and replaced the evap, which had a bad weld at the inlet and was (probably) my original leak point, as well as replaced the dryer and tube, and put on a junkyard compressor & clutch.

Now at 168k, I'm ready to spend a little extra money getting it working, since I work at a shop and have access to shop air and have decent tools.

I've read about converted systems running too high and needing a larger condensor + a cooling fan in front, so I wanted to replace the condensor with one made for 134. Also wanted to have the 134 hi and low switches to keep my system pressures ok.

I just need help being pointed in the right direction. I don't know my way around 2nd gen Ex's cooling systems and what all I would need to replace.

Side question, on a 1st gen, is the small metal cylinder inline on the hose from compressor to condenser a filter? Couldn't ever decide what it did so I left it alone.

Thanks in advance!

 

[TheJackal]

Hello,
I don't know much about the first Gens so I don't know what's interchangeable.

You may want to leak check again because R-134a can leak out places R-12 can't. You may need to consider replacing some hoses. Old O-rings may need to be replaced with the green ones.

The metal can might be a muffler; it can't be flushed.

 

[ranger7ltr]

Is the repaired system just sealed and not running?

I see you replaced accumulator/compressor/evaporator and tube[orifice tube?] at this point so you are not too far from completing the task...

If you want to covert to R-134a you should replace the R-12 condensor with one designed for R-134a...They offer better heat transfer than a typical R-12 condensor... And that will keep the system pressures in check with R-134a which does run at higher pressures than R-12...And depending on the hose condition, you might want to replace the rubber sections of your hoses now with R-134a compliant hose.. The old hoses would probably hold and not leak thanks to being coated with oil but if they are hard/brittle/leaky/questionable in any way, have them rebuilt while the system is apart...

You should replace the orifice tube with one for R-134a and most current accumulators are equally capable of working with R-12 or R-134a... Since work on the system has been done did you already install refrigerant oil into the system before closing it up?

The big difference is that R-12 uses a mineral oil to lubricate the compressor while R-134a will not move mineral oil and requires either an ester oil or a synethetic refrigerant oil like Polyalpha to lubricate the system..If you installed oil in the system and ran it, a system flush is in order to remove the old oil...Some claim that the old oil will puddle in the system and stay there while ester will flow throughout with R-134a...Personal choice is to remove the old oil but that is up to you...

Also the o-rings in the system should be replaced with correct ones for R-134a... Most R-12 orings are black and I have only used green o-rings with R-134a...And when you fill the system use 70% of R-12 capacity as a starting point after evacuation and then monitor vent temps, high and low side pressures as a guide to know when to stop filling the system...

I usually use a 2.3x-2.7x ambient temperature for high side pressure as a guide...Oh I have not seen an extra cooling fan on the condensor of an Explorer and one should not be needed if the engine cooling fan is in good shape.. If it is not, replace it...The engine will deliver great airflow at rest if it is in good condition especially when the engine temps start to climb...

BTW, the metal canister is a muffler like Jackal said and flushing it is a no-no...And don't flush the accumulator either...Replace it...And you may need to replace the low pressure cycling switch from a later model Explorer if you go to R-134a...