XF Aircon Help Needed - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

BOF · 01-08-2002, 01:56

My brothers 87 XF has a problem with the aircon, it's cold and works well it just doesnt work for long, for example it will work when turned on for about 30 seconds then it throws itself out for about 15 seconds, then click and it's back on again cold as ever, I gather this must be activated by some kind of thermostat which throws the aircon clutch in and out when it reaches a set temp, how can this be repaired or adjusted so the aircon isnt clicking on and off several times a min as with the current setup the car never gets really cold and the cold air isnt blowing long enough.

Thanks

Fairlane Boy · 01-08-2002, 04:58

either its got too much/not enough refrigerant in it, the hi/lo pressure cutout switch is stuffed, or the thermostat. possibly the compressor clutch too.

use the process of elimination.

botch · 01-09-2002, 00:07

By saying that it is cold, im assuming that the compressor cuts in for a while when first turned on, the low pressure pipe (big one at the firewall) should be ice cold after running for a litle bit. If not then u may be low on gas.

Another thing to check is that there is vacuum to the heater tap when the ac is on and that only one hose on the heater tap should be hot. The other one, that goes inot the heater box should be mildly warm but not HOT. If both hoses going to the heater core are hot then try clamping the heater hoses and see if this makes the ac work better.

Then check the a/c thermostat. It is mounted behind the glovebox and you have to remove the plastic lever that runs off the hot/cold cable (should be screw in middle). The thermostat should have 2 screws holding it into the plastic heater box assembly. The thermostat should have the probe end inserted into the heater box and hopefully into the condersor inside

Thermostat has 2 wires plugged onto it. Check with test light. One should have power to it when ac switch and fan is on. The other should have power when a/c is running, but cut out when its cold enuff (around 4 degrees at the vents). If you continuosly have power no matter what then either the probe is not in the evaporator or the thermostat is faulty.

By holding the revs up to the 2000 mark the a/c should come in and pull down to about 4 degrees at the vents, then cut out and cut back in again at about 8 to 10 degrees.

By bridging out the thermostat with a piece of wire, this should make the compressor cut in and pull down to the 0 degree or colder temp at the vents. by doing this the evaporator will freeze up and you will eventually lose air flow through the vents cos it will turn into a big ice block.(uses heaps of fuel too)

Check these things and see how you go. Let me know if i can help some more!

XR_Strider_GuY · 01-09-2002, 00:29

Quote:

Originally posted by BOF 351
My brothers 87 XF has a problem with the aircon, it's cold and works well it just doesnt work for long, for example it will work when turned on for about 30 seconds then it throws itself out for about 15 seconds, then click and it's back on again cold as ever, I gather this must be activated by some kind of thermostat which throws the aircon clutch in and out when it reaches a set temp, how can this be repaired or adjusted so the aircon isnt clicking on and off several times a min as with the current setup the car never gets really cold and the cold air isnt blowing long enough.

Thanks

Just wondering when you mean the Aircon cuts out, is the fan still running or does the fan die out as well?

Jase_ELXR8 · 01-09-2002, 01:48

Check the thermostat first, failing that, compressor clutch or TX valve