Ford introduced the Explorer in 1991 with a 4.0-liter V-6 that produced 155 horsepower. It was not until 1996 that it was available with a 5.0-liter V-8 producing 210 horsepower. Removing the air compressor on this vehicle requires a reclaiming machine to withdraw the Freon from the system. It is illegal to open the system and contaminate the atmosphere with fluorocarbons. The system can be charged without the reclaimer as long as a vacuum pump is available. Along with a new compressor, the accumulator and orifice tube must also be replaced or it will void the warranty on the compressor. New refrigerant oil must be added to the compressor and the system to replenish that lost during removal.
Drive the vehicle to a service facility to have the Freon evacuated from the system. Raise the front of the vehicle with the floor jack and place jack stands under the frame. Lower the vehicle onto the stands. Disconnect the clutch wire at the front of the compressor by pulling the two ends apart.
Remove the single bolt securing the manifold hoses to the rear of the compressor, using a socket. Pull the manifold hoses off the compressor but do not lose the O-rings. Remove the accessory belt by inserting the ratchet into the slot on the belt tensioner pulley. Push the pulley away from the belt and remove the belt from the air conditioning pulley only.
Remove the four bolts securing the air compressor to the engine bracket using a socket. Remove the air compressor. Remove the drain plug on the side of the compressor and drain the oil into a cup. Remove the drain plug on the side of the new compressor and add the same amount of oil that drained from the old compressor, plus 2 ounces. If no or very little oil has drained from the old compressor, add 7 ounces of refrigerant oil to the compressor. Install the drain plug and stand the compressor up on the clutch while completing the rest of the work. This will allow oil to soak the front seal, preventing any possible leaks.
Locate the accumulator, which is located on the passenger side of the engine compartment. Look at the new one and it will be easy to find. Pull the plug out of the low-pressure sensor. Remove the bolt in the clamp that holds the accumulator in the mounting bracket using a socket.
Loosen the 22 mm and 27 mm lines at the top of the accumulator using line wrenches. Lift the accumulator out of its bracket.
Uncap the new accumulator and pour 4 ounces of refrigerant oil into one of the two ports. Place a small amount of refrigerant oil on both O-rings on the hose connectors. Install the accumulator into the mounting bracket and align the ports. Thread the nuts clockwise to tighten the lines. Tighten the clamp bolt with a socket. Plug in the low-pressure sensor or cutoff.
Look at the small-diameter high-pressure line coming out of the condenser. You will notice the line has a pair of dimples in it just behind where the line parts with the use of two connectors (where the high-pressure metal line comes from the condenser and plugs into the same line that continues to the evaporator). Separate the line at this point using the A/C line separator tool.
Pull the orifice tube from the line leading to the firewall using needle nose pliers, making sure to notice how it comes out. Install the new orifice tube in the same manner and plug the two lines together again until they snap lock.
Install the air compressor and tighten the four bolts. Place some oil on the O-rings on the manifold and install the manifold lines to back of the compressor. Tighten the single retaining bolt with a socket. Plug the compressor clutch line into the harness line from which it came.
Push the belt tensioner away from the belt and install the belt. Relax the pressure and allow the tensioner to apply tension to the belt. Raise the front of the vehicle and remove the jack stands, then lower the vehicle.
Install the manifold gauges with the blue hose going to the large suction line Shrader valve and the red hose to the smaller high pressure line Shrader valve. Make sure the valves are in the off position.
Connect the center yellow line to the suction port on the vacuum pump. Turn the pump on and open both valves on the manifold gauges. Allow the system to drop into a vacuum for 30 minutes or until it reaches 30 inches of vacuum on the blue gauge.
Close both valves on the manifold gauges. Turn off the vacuum pump. Observe the gauges for several minutes to confirm there are no leaks. Disconnect the yellow hose from the vacuum pump and place it on the Freon container. Open the valve on the container of Freon. Momentarily open the yellow hose connection at the manifold set to purge air from the yellow charging line and tighten the fitting again.
Open the blue valve only on the manifold gauges to charge the system. Never open the red valve because pressure in this line far exceeds that of the container and will cause an explosion. The pressure will build on the gauges to approximately 120 psi on the high side and 20 psi on the low side. It is not that important at this point because the intent is to charge the system initially enough to close the low side cutoff valve. If this does not close, the compressor will not come on. It needs about 20 psi to close. Charging the air conditioning system with small cans makes measuring the amount of Freon difficult. This system however, will work just as well as long as you pay attention to the gauges. The target pressure for an 80-degree day is 30 to 35 psi, give or take only 3 pounds on the blue low side. The high side will be 230 to 250 psi. Over 270 is a problem on the high side -- this means you probably have a blockage. Over 40 on the low side is also a problem if either is high and no cooling is present. If this happens then the system must be evacuated again and flushed of debris.
Start the engine and turn on the air conditioning system. Turn the blower on high. Place one hand on the accumulator as you watch the low- and high-side numbers -- do not exceed them. When the numbers are close (25 low and 230 high) pay attention to the accumulator. When the system becomes fully charged there will be a very sudden drop to freezing in the evaporator. It will get ice cold quickly. Turn off the valves on the manifold gauges. It is charged. Disconnect all the hoses and install the blue and red caps on their respective lines.
