I have a 92 explorer a few years ago i got a new compressor and had it converted to R-134, the past few days its been nice out in the 60's outside but inside the truck its like 90, decieded to try the ac blows warm the compressor comes on but for about 3 sec or less, and cycles on and off very frequently, so am assuming it needs to be charged. What kind of kit would you reccomend i buy and how much should i charge it to get the most amount of cold air, also what temp is ideal to do this at, i know it expands when it gets hotter outside. Also should i take the pressure reading with the compressor on or off? And about how long should it stay on and about how long before it comes on again? Thanks

 

Are you familar with 134a and do you have the gauges, and tools to work on the system. If you don't take it somewhere.

 

It sounds like you have a leak. So it would be best to get that fixed before recharging or you'll always be needing to do it again. Good luck, John

 

You should have the leak fixed first.

A leak can sometimes be visually spotted by the presence of PAG oil at or near the leak. The refrigerant and oil travel through the system together, therefore as R134 escapes so will some oil. Check all of the connections, inspect every inch of hose, and every component for an unusual patch of oily residue. If everything is tight and dry you may be leaking out the front seal of the compressor, check the face of the compressor clutch for oily residue.

Since you are retrofitted to R134, I would suggest taking it to a Pro. The cost will be fairly resonable as compared to an R12 system.

The tools needed are far to expensive to buy, unless you are planning to keep a small fleet of older vehicles, then let a pro handle it. It is too easy to screw an expensive system up.

If you feel like taking a guess, I would buy one can of premixed R134 with a small charge of PAG oil in it. You will also need the adapter hose that fits between the can and low side service port (blue cap)NOT the RED!!! Do not try to fill the system via the red port!! There should be about 30 psi at the blue(low side ) port and there will be anything up to 250 psi at the red ( high side ) port. If you put a can onto the red port it probably will blow up in your hand because of the high pressure. It is highly likely that anything you can buy to charge the system will not fit over the high side connector, the high and low ports of R134 systems are two different sizes.

I would follow the directions on the can and stop charging as soon as the clutch goes into steady cycle and the air blows cold.
Good Luck

 

OK thanks for all the tips, i think i have a leak on the high side, right around the red port and over by the flilter i see oily residue so about how much should i expect to pay for that line to be replaced and for it to be recharged?

 

A buddy of mine had the gauge so we hooked it up last night to the low side it was reading 65psi, with the engine warm and running but ac off, when we turned the ac on it jumped down to about 25psi, little less, compressor shuts off in about a sec, then come back on when the pressure went up to about 45- 30 PSI, so my question is, does it sound like its underchaged or what or is it just not working also, i know the low side over by the pressure checker the line is suppose to get cold it does not, so it must be undercharged correct??? Also the you cant mess up the fittings on the high side are differant size than the low side, i also saw a ac recharge kit at auto zone about 30bucks comes with gauge and plenty of R134a, i dont really want to spend a lot to fix the hoses or anything, as long as it works, and plus i dont think its that big of a leak i had it charge 2 years ago and it still has pressure, also the temp outside was probally around 60 and engine was hot, i have not decieded yet what am going to do any more suggestions?

 

Your pressure of 25 psi means that the temperature of your low side is about 30 degrees F. You need to add R134a until you increase your low side pressure to about 33-35 psi and it holds steady while the compressor is operating. Your compressor is being turned off and on by the low pressure switch. It comes into play when you have a low charge, like you do, to protect your compressor. I would add R134a only and not worry about the oil. Put your A/C on "Max" and run your engine at high idle when you add the refrigerant. Try not to add more than it needs because it will blow warm air with too much charge in it. What you feel coming out the vents can be a good indicator. I think you are right about your leak not being that bad. I add about one can a year to mine.

 

Great thanks Joe P,

 

you need recharged.


92 ford ac systems leak.

spring locks assemble quick tho

 

One good method to tell when you are close to full charge is the condensate drain line will begin to drip water on the pavement below the truck. Typical to drip at 2-5 seconds per drip. This is best observed at the rear of the right front tire. (When the systems are under charged the evaporator coil freezes up and no condensation is dripping.) This should also coincide with 40-45 PSI on the suction side at approx 1500 rpm on the tach.

Alan

 

MY r134a is on its way autoparts stores in my area have not gottne it in yet so i got it off ebay, whats the ideal temp to charge at??40, 50, 60, 70, just want to make sure i have ac working befor the real heat comes

 

It should be at least 70 deg to get the charge rite! Another way is to feel the filter drier ( the aluminum canister) with your hand while charging and when the cold makes its way about 3/4 up you are close enough!!
Good luck
Jasontrucks
btw service manager HVAC shop