A/C not getting cold

[03wr250f]

I have a 89 ford and even on max a/c and cold it barely if at all gets above outside temperature. The heat works ok but nothing phenomenal. I have had several trucks (gassers) and all of them will bake you out or freeze you. My last thing is their is no difference in fan settings the first three so hardly anything, and the last one or high puts out marginal amounts of air.
Any suggestions for me to check, or any ideas are greatly welcome and appreciated.
thanks in advance
~aaron

 

[chris142]

is there refrigerant in the system? is the ac clutch engaging? is there a frost line back to the compressor? is the blower spinning? is the evaporator plugged with dirt? got black death?

 

[icanfixall]

Best question is the clutch engaging and disengaging all the time. That usually means the freon charge is low. then you need to know what type freon you have. Hopefully is R12 and not R 134 or whats the worst.. A mix of other freon thats not serviceable by any shop.

 

[lotzagoodstuff]

Check that your blend door is operating properly. The door seals are notorious for falling apart over time, but I would also make certain that you can physically see the door opening and closing, and while your inspecting, make sure that Alvin & The Chipmunks haven't built a home in there. Realistically, the only real way to tell what's going on is to put some gauges on your refrigerant system and see what you got, but it is strange that you've got marginal heat and a/c, hence my suggestion for looking at the blend door.

Good luck

 

[OLDBULL8]

Welcome to the Oilburners.

I have a 89 ford and even on max a/c and cold it barely if at all gets above outside temperature.
You are probably low or out of Refrigerant. There should be a lable somewhere under the hood showing what type of Refrigerant you have. Most likely been changed over to R134A

The heat works ok but nothing phenomenal. I have had several trucks (gassers) and all of them will bake you out or freeze you. My last thing is their is no difference in fan settings the first three so hardly anything, and the last one or high puts out marginal amounts of air.
I would pull the fan out and check for trash in there. The fan speed resistor may be bad, it's located behind the pass side kick board.

Any suggestions for me to check, or any ideas are greatly welcome and appreciated.
thanks in advance.
There is a 2 pin connector on the accumulator, that is the black 4"x 6" can by the firewall, jumper that out to see if the compressor clutch energizes, have to do this with engine running and Hi fan ON and Max cool. If it kicks in and runs the compressor, then you need to add refrigerant. Add refrigerant until a frost appears on the large line at the accumulator. If the refrigerant is R12, it's almost impossible to get, then it should be changed over to R134A. A kit can be bought to do that with instructions.
~aaron

,

As suggested above on the blend door. It's operated by a vacuum motor on the pass side by the firewall, check for vacuum hose leaks to it.

 

[dgr]

Your blower motor resistor is shot. It reduces power to the fan motor on all settings except high. When the solder joint on it blows, the fan will only operate on high. $30 at your local parts store. I would pull the blower motor and dig out the years of compost that accumulates below it and in the heater and evap core. That was the problem on mine. It was bad enough that it would smell like burning grass when the fan got spinning in the old dry leaves.

 

[03wr250f]

OK how do I check the things you guys suggested
And the clutch is not engaging at all
And it says it has r12 in it

 

[03wr250f]

Welcome to the Oilburners.


,

As suggested above on the blend door. It's operated by a vacuum motor on the pass side by the firewall, check for vacuum hose leaks to it.

When you say two pin connector what is the accumulator, and how do you jumper it out?
Next their is no frost line, and where is the fan and transistor located

 

[dgr]

Fan and Resistor is located on the firewall. Back passenger corner of the engine bay.

Pressure switch -- follow your A/C lines until you come to a pressure switch screwed in it. It is a 2 wire connector. You pull the connector and put a wire between the two wire connectors inside of the connector.

I would assume you have no or not enough R-12 in your system if the clutch isn't engaging. The days of slap some R-12 in and let it leak out in 6 months are long past. You need a set of gauges to see if you have refrigerant in your system. A quick depress of one of the schraeder valves on the A/C lines would tell you if there's some refrigerant in there and might get the white vans showing up at your house and your kitten stomped by some feds.

 

[tbiagent69]

I check in the forum somewhat frequently but rarely post. I'll be getting an 87 IDI in the next month, so you guys may see me around more

Anyway..

I would say to use a manifold gauge set and check to see if there is pressure in the system. My guess is no, or hardly any.

If there is above 12 PSI in the system, then the compressor should be able to click on, even for a short time.

If it IS above 12 PSI, check to make sure the low pressure cutoff (which is on the right side of the engine compartment by the radiator core support IIRC) has power and continuity in it. If it has power on both sides, then you should check the compressor for power and continuity.

If it is at 0 pressure, look around for wet spots on all the AC lines. The system is pretty basic and easy.. Compressor, hose from compressor to condenser, condenser to evaporator (with the orifice tube between it), then the evaporator to the filter / drier (or accumulator) and then from the filter/drier to the compressor.

Check each junction for leaks. Any oil residue is likely a leak. Anything wet is probably the source of your problem. On the soft rubber lines there are usually crimp fittings, and I've seen those go bad also. The condenser is a good place to check because it's basically the first thing that bugs and rocks hit when they go through the grille.

The orifice tube is a pretty good indicator of system health. It's the first filter in the system and will grab all the ****** that floats through the system. You can check it by using one of those spring connector tools on the high pressure line going in to the firewall to break the seal, then there is a double o-ring fitting that you have to twist apart.

The orifice tube can be pulled out with pliers. It has screens on the input side that from my experience will clog with junk if your compressor is going out. If it's fine, then fix whatever leak you have and put it back together.

Once all that is done, and you've fixed the leaks, then you're supposed to pull vacuum before charging the system. I usually pull vacuum for a half an hour or so, then let it sit for a while and make sure that it hasn't leaked before I fill it up.

I have used the variable orifice valve as opposed to the fixed orifice tube and I personally think it is a great investment. Some people may not like them for whatever reason, but I've always had great luck with them.

Also, if you're going to be leaving the system open for any amount of time make sure you plug the hoses with a rag or something to make sure you don't get a lot of air circulating in the system. The filter/drier has a dessicant in it which will absorb moisture in the air.

Umm... also, I'd say to replace any o-ring you come in contact with when taking the system apart. When you replace them I'd suggest dipping them in compressor oil to get a good seal and reduce the chances of pinching the o-ring upon reassembly.

 

[tbiagent69]

Oop..

I just realized that I said the wrong place for the low pressure cutout switch. The liquid line (high pressure) would be on the right side of the engine compartment (driver's side). The low pressure cutout switch will be on the low side, likely attached to the filter/drier somewhere.

Either way, there will probably only be 1 switch on these. I had a R12 bronco that did not have a high pressure switch, but the compressor had a built in pressure relief valve to prevent overcharging.

 

[03wr250f]

Alright thanx guys I am away for the weekend but when I get home I will start with the list y'all left me. Thanx especially tbiagent69 for the detailed reply. I pulled the blower motor And cleaned out some build up, found out the motor has been replaced once, and also have a new resistor that I need to go pick up. While I was in their I wiped down everything and then forma-gaskted the motor back on so thank you so much for the info and I will keep you all posted.

 

[03wr250f]

Alright when I got home replaced the blower motor resistor and life is good. With the motor housing clean and a new resistor I have 4 fully functioning fan speeds And it gets cold, so I am happy with it. Thank you all so much for the help and advise I really appreciate it.

 

[tbiagent69]

Did you jumper the low pressure cutoff? If so, that's only a temporary fix and you should definitely not run it that way. Make sure you have the proper amount of refrigerant in the system or you'll end up with a very expensive fix. From my experience the switches rarely go out.

 

[03wr250f]

Well I have checked it over and all looks good thanks soo much guys