1994 ranger ac project


swamprat

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So I am starting an AC project on my 1994 Ranger. It has never worked for the few years that I had the truck. I believe it has R12. There are no labels on the rad support. I did try a can of AC Cool 134 that son had and it wouldn't fit on the port. So should I retro fit to 134 then trouble shoot the problem of why it doesn't work? I do know the clutch doesn't kick on.
 


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Denisefwd93

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swamprat

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so the conversion kit looks like new ports that screw in place on the old one . flush kit and change orings and dryer? Purchase a vacuum pump and regulater and add 134 and see what happens? I generalized that but is that the idea where to start?
 

Denisefwd93

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the 134a adapter connectors screw over top of the old R12 connectors. I would at least pressurize the system and and see if it leaks out in a few days.

Assuming you have no leaks continue on

remove the compressor dump the oil, flush that, remove the filter drier receiver dump oil & flush it,

put it back in because you're going to be taking it out again. (Or not)

Add proper amount of pag oil, some refrigerant short out the low pressure and run it a while then take it all apart and flush all again! ( Or not)

I think I would also include replacing the orifice tube, they're pretty inexpensive.

Through all this you should be able to learn how to use the gauges, vac pump, and basic properties of how refrigerant works from liquid to gas, gas to liquid, how to read the gauges how to read the tp charts which are the same as the gauges.

All the above is just my suggestion it's not written in stone it's your truck your decisions and any free advice is worth what you paid for it :)

Yes people do the conversion don't take anything apart flush the oil run it and flush it again. Hopefully the system won't suffer from Black Death
 

swamprat

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I do have 134 a so no conversion needed. I don't know what I was doing wrong with the other can. I added some 134a according to the gauge on can it should be enough to work. The compressor clutch still not engaging. Checked connection to AC compressor with volt meter and got nothing. So I need to track down why Im not getting power to it. Could it be the pressure switch?
 

Denisefwd93

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stock, may get leveling springs in front "somday"
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I do have 134 a so no conversion needed. I don't know what I was doing wrong with the other can. I added some 134a according to the gauge on can it should be enough to work. The compressor clutch still not engaging. Checked connection to AC compressor with volt meter and got nothing. So I need to track down why Im not getting power to it. Could it be the pressure switch?
Without knowing the actual pressure it's hard to know if the low pressure switch is working or not, I would not go by the can, I would go by the people trying to help you,

anyway use a fused wire directly from the battery to the clutch and see if it in engages before you tear things apart good luck
 

swamprat

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yes I realize the can guage is not the proper way but thought it might get it close enough to see if I can get the clutch to engage. The relay tested good so I went to the low switch. I jumped the switch and the clutch engaged. Outside temp is 78 and at vent with ac on is 57. I think the thermometer is reading a little low
 

Denisefwd93

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stock, may get leveling springs in front "somday"
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Oh well that's good! Air in air out should be 15 to 20 degrees lower on the evaporator side and higher on the condenser side which is hard to check because it's in front of a radiator.
It should cycle on the low pressure switch if it's not hot outside and if the line going back to the compressor is cold, refrigerant charge is probably okay or close to it. Low pressure switches don't go bad very often but it could be! which means losing the charge to change it.

I don't know if they make a piggyback fitting for automotive but if they did you could piggyback a low pressure switch instead of dumping the R charge to replace it. Also I don't know I haven't really looked on the Ranger, but my older GM cars had an adjustable low pressure switch just a matter of turning a screw out or in.
 
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swamprat

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still got to check for leaks and test high pressure switch
 

swamprat

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Found a very small leak on high side. Couldnt tell at first if I was seeing the o ring glow or if there was a leak. Guess I will get an o ring kit and replace low side pressure switch.
 

Denisefwd93

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Ford
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2WD / 4WD
4WD
Total Lift
stock, may get leveling springs in front "somday"
Tire Size
235
Be happy, I've been in the HVAC business my whole life, the refrigerant in my 94 extended cab leaks out in 24 hours I still haven't really worked on it but I'm getting closer, lol
Found a very small leak on high side. Couldnt tell at first if I was seeing the o ring glow or if there was a leak. Guess I will get an o ring kit and replace low side pressure switch.
 


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