Problem with Ford 1998 Ranger A/C

[Tray420]

Hi fellas,I need some help getting my moms 98 ford Ranger a/c working and I thank you all in advanced for some advice.anyway the a/c in the truck will blow cold air for 5-15 minutes then gradually just air...from what i read I think its probably low on coolant...today i checked the clutch and it engages.If I turn the a/c off and then back on It doesnt engage and I'll here a poping/clicking sound from the dash.but if i give it a minute,start the truck back up and turn on the a/c it will engage.again thank you now in advance for anyone who can help with some advice...trust me I'm tempted to just add some coolant but it is my moms truck afterall and I aint taking any chances Peace

 

[franklin2]

Roll the windows down in the truck, start the engine and turn the A/C on. The clutch should engage right away like you said, and as hot as it's been and with the windows down, the clutch should stay engaged. Make sure you put the blower on high.

After the 15 minutes or so, if the clutch turns off, leave everything alone and see if it cuts back on by itself. If it does, and then runs for a little bit and then cuts off again, you are just slightly low on refrigerant, just add a little bit till it quits cutting off and stays running.

 

[RonD]

AC in a car/vehicle works the same as AC in a house, or refrigerator or freezer

The compressor does what it sounds like, it compresses "freon"(coolant) so its at a HIGH PRESSURE
Then the high pressure "freon" is released slowly into the LOW PRESSURE side which causes the cooling effect

There is a high pressure cut off switch, and a low pressure cut off switch
High pressure switch prevents lines and hoses from BLOWING OFF/Splitting
Low pressure side prevents compressor from "running dry" and burning up

Compressor would be turned off by either switch in normal operation
Once there is enough high pressure "freon" compressor can shut off for a bit until enough pressure has been released

If low on "freon" then low pressure side may be running out causing compressor to shut off

AC system doesn't shut off when you turn off the engine/key
Any high pressure still in the system keeps flowing slowly to the low pressure side, until pressure is EQUAL in both sides
So shutting the engine off may have allow enough "freon" to flow to the low pressure side so system could be activated again

 

[Tray420]

Roll the windows down in the truck, start the engine and turn the A/C on. The clutch should engage right away like you said, and as hot as it's been and with the windows down, the clutch should stay engaged. Make sure you put the blower on high.

After the 15 minutes or so, if the clutch turns off, leave everything alone and see if it cuts back on by itself. If it does, and then runs for a little bit and then cuts off again, you are just slightly low on refrigerant, just add a little bit till it quits cutting off and stays running.

hey bud i did like you said and sure enough the a/c cut off.i hooked up the guage portion of the recharge kit and the guage says its overcharged...not sure what to make of it.moms said her neighbor tried to recharge it for her a few years ago so im guessing ol boy got a lil happy while he was fillin the a/c...so if the system is over pressurized what can i do about? i appriciate both yall takin time to help me out...youre also helpin my sweet lil mom fyi..thanks again!

 

[Tray420]

AC in a car/vehicle works the same as AC in a house, or refrigerator or freezer

The compressor does what it sounds like, it compresses "freon"(coolant) so its at a HIGH PRESSURE
Then the high pressure "freon" is released slowly into the LOW PRESSURE side which causes the cooling effect

There is a high pressure cut off switch, and a low pressure cut off switch
High pressure switch prevents lines and hoses from BLOWING OFF/Splitting
Low pressure side prevents compressor from "running dry" and burning up

Compressor would be turned off by either switch in normal operation
Once there is enough high pressure "freon" compressor can shut off for a bit until enough pressure has been released

If low on "freon" then low pressure side may be running out causing compressor to shut off

AC system doesn't shut off when you turn off the engine/key
Any high pressure still in the system keeps flowing slowly to the low pressure side, until pressure is EQUAL in both sides
So shutting the engine off may have allow enough "freon" to flow to the low pressure side so system could be activated again

hey man this is what i replied back to the other guy whoy answered me, hey bud i did like you said and sure enough the a/c cut off.i hooked up the guage portion of the recharge kit and the guage says its overcharged...not sure what to make of it.moms said her neighbor tried to recharge it for her a few years ago so im guessing ol boy got a lil happy while he was fillin the a/c...so if the system is over pressurized what can i do about? i appriciate both yall takin time to help me out...youre also helpin my sweet lil mom fyi..thanks again!
..............any thoughts?...oh and thankyou for takin time in the first place for your last reply!if youre in virginia,i owe you a beer...or some green

 

[Ranger850]

hey bud i did like you said and sure enough the a/c cut off.i hooked up the guage portion of the recharge kit and the guage says its overcharged...not sure what to make of it.moms said her neighbor tried to recharge it for her a few years ago so im guessing ol boy got a lil happy while he was fillin the a/c...so if the system is over pressurized what can i do about? i appriciate both yall takin time to help me out...youre also helpin my sweet lil mom fyi..thanks again!

I would find out what the pressure is supposed to be, and release enough pressure to get it to that point.

 

[RonD]

Most likely a clogged orifice filter/tube, or other blockage in high side of system

Should be equal pressure in both sides if system sat for a few hours, usually around 100psi but REALLY depends on outside temp
As said AC is an "open" system there are no shut off valves, once compressor is off the pressure in the system keeps flowing from high side to low side until they are equal pressure

Might be time to drain the system to change the receiver/drier and orifice then refill
If it was holding high pressure then probably no leaks

 

[franklin2]

If you hooked the gauge you had up while the compressor was off, it will say over charged, since the compressor is not running.

You didn't do the rest of the test did you? Did you wait and did it come back on again after a little bit by itself?

If you are going to use your gauge, only read it with the compressor running. The compressor will suck down the low side while it's running, and if the pressure is too low, the low pressure switch will cut it off. But since you have the gauge you can watch it also, if it's low the gauge will read low till the compressor cuts off, and then the pressure will start to rise by itself.