So the compressor blew up on my 1993 f150 4.9L 5spd 4x4 shortly after I got it (PO had it disabled and I put in the fuse, then the clutch seized 2 days before I had to drive 1100 miles to college)
I bypassed it with a bypass pulley and threw the compressor out (kept the bolts)
That was approximately 18 months ago. The lines have been sitting open since then and because I will be working in LA again this summer I would like to get working AC.
I have decided to convert it fully over to R134a seeing as most of the components need to be replaced anyway.
I plan on ordering the following list of parts (for a 1995 f150 to get R134a compliant) from RockAuto soon so I can do the work over Spring Break. Is there anything missing from the list, and specifically what new switches or sensors will I need if any. I would like to replace every component in the system to ensure it can handle some brutal summers. Also, any tools I might need I would like to order soon.
AC Conversion (R12R134a)
Condenser $70
Mounts (4x), $6 each
Filter $35
Evaporator $45
Misc Adapters and switches $20 (SUGGESTIONS PLEASE)
O rings and gaskets $10 for extra set, might be included with compressor
Lines (Approx $100 Total)
Condenser to Evaporator (Liquid Hoses) $25
Suction and Discharge (Manifold Hoses) $75
Compressor (GPD) ----- $145 Includes Everything Below
Drier/Accumulator
Orifice Tube (RED)

Vac and charge at shop $100 ??

Total Approx. $550

THANKS!

 

UM.... You do NOT need all those parts

All you need is what is broken(the clutch)

Replace the office tube

Draw a vacuum

put in PAG oil and then 134.

DONE

No need to change EVERYTHING

 

I junked the compressor, it had been sitting dead for who knows how long before I got it. The rest of the system has been sitting open for the better part of 2 years and was leaking like a sieve before given that thee was no freon in it when I took the compressor out. And the condenser is still of the r12 size so having the larger r134a version would help in traffic.

 

the 134 systems had a high pressure cut-out switch mounted on the manifold of the compressor. i cut the wire to the compressor and routed through the switch. the low pressure switch on the dryer is different, make sure the one you get is for the 95 becaues the threads are different. my compressor came pre-filled with the right amount of oil. I had some line connector issues, but that was going from 90 to 95

 

Alright, I'll add those switches to my list.
Does anyone that has converted a 92/93 know if I need to splice wires or can I make a run to the scrapyard to grab a pigtail that will accomodate the compressor switch for r134a?

 

All you need is compressor, a dryer and office tube.

Anything else is wasting money

 

Flush the system! R12 systems use mineral oil, while R134a uses PAG. You could ise ester oil (better on seals).

Replace your valve cores with new ones (biggest leak spot), and get conversion fittings for the r134a hose connections.

 

I disagree on this. He needs barrier hoses because R134a will seep thru the nitrile hoses on his truck. The R134a condenser is optional, but provides about 50% more surface area than your stock R12 condenser - this will help cooling performance at low speeds (such as sitting at a stoplight).

The only components that are the same between R12 and R134a systems, from the factory, are the compressor and evap core.

You can do the job more cheaply, as Brad suggests, but performance will suffer.

 

I did the same two summers ago with the Rockauto parts. Autozone has all of the "rental" tools you'll need for the job. Gauges, vacuum pump, orifice tube puller etc. You basically pay the tax to rent them as you get your money back when you return them. It will save you a lot of money and it's pretty easy to do yourself. I bought A/C system cleaner and ran it through the lines as directed to get all of the black death out of them. Autozone even had the sprayer that hooks up to my air compressor to run the cleaner through it.

I don't know about the lines etc, as mine is a '96 and was already r134, but I'd trust what others say on this forum about changing them.

I'm in Houston and I've been very happy with the performance of the parts so far.

 

If the compressor seized up internally, then it is absolutely necessary to replace the condenser, and flush out or replace the evaporator and all lines/hoses. When the compressor seizes, it grinds itself up inside and spews metal shavings throughout the system. You need to remove all shavings, or else it will chew up your new compressor and you'll be back at square one. Like I said, evaporators and lines can be flushed out, but condensers have so many small passages and nooks and crannies for shavings to get stuck, that they're basically impossible to flush out and you're much better off replacing with a new one.

 

Glad to see so much input, I will be replacing everything because I have no idea what condition the system was in prior to the clutch failure (It did not sound healthy)
Does anybody have some part numbers on the High and Low Pressure switches? I'm having a little difficulty finding anything reliably, there's one or two results on the major mcparts sites but they seem "universal"
Here's my final list from RockAuto for future searchers and anybody to let mknow anything I missed. I went with GPD parts because Four Seasons had some bad reviews online. And the Motorcraft Compressor was spendy.




THANKS!

 

The high pressure side is relief valve that will vent pressure if it's too high. The low side pressure switch screws into the dryer/accumulator, it's not under A/C, look under eletrical switches and relays, they call it a clutch or compressor switch. Motorcraft part YH552.

The high side relief valve is built into the hose that feeds the compressor.

 

That is not 100% correct, there is an electrical high pressure cutout switch:

 

I'm only seeing it as a $25-$30 switch and not a factory looking connector. I'll make a run to a yard and see if I can grab the pigtail that goes from the harness to the high pressure switch to the compressor. I can take a look at any switch there as well, or just get it from a parts store while I wait for the main order

 

Four Seasons 20916 High Cut-Out Pressure Switch