Repair Procedures For Evaporator
A. Removal of Evaporator from Vehicle1. Disconnect the battery negative (-) terminal.
CAUTION:
On vehicles equipped with electronic memory radios or electronic clocks, be sure to record the customers' channel selections (AM/FM) prior to disconnecting the negative terminal. Reprogramming the radio and resetting the clock will be necessary after repairs have been completed.
2. Slowly discharge the refrigerant gas (R-12) from the system.
NOTE:
If oil comes out during discharging, make sure to return the same amount (using fresh refrigerant oil) back to the system.
3. Using two (2) wrenches for equalized support, disconnect the liquid and suction fittings from the evaporator.
NOTE:
Cap open fittings immediately to keep moisture out of the system.
4. Remove underdash cover and glove box (where applicable).
5. Remove all A/C wire connectors from evaporator.
6. Remove right and left seal plates.
7. Remove nuts/bolts securing evaporator, and remove unit from vehicle.
B. Disassembly of Evaporator Unit
1. Mark the location of the thermostat's capillary tube or thermistor probe in the evaporator core fins, then remove from the core.
NOTE:
Proper positioning of the probe during installation is extremely important for proper cooling.
2. Remove clips, screws and evaporator core from upper and lower case.
C. Expansion Valve and/or Core Replacement
1. Remove the following items:
a. Prestite Tape
b. Clip holding Control Bulb
c. Equalizer Line Fitting (where applicable)
d. Expansion Valve Fittings (use two (2) wrenches for equalized support)
2. If evaporator core replacement is necessary on the 626, transfer the super heat switch and the wire mesh screen (if available) to the new core. (Use new foam tape to hold the wire mesh screen.)
D. Assembly & Installation of Evaporator Unit
1. Follow the removal procedures in reverse order and note the following items:
a. Lubricate all fittings and O-rings with refrigerant oil before connecting them.
b. Use new O-rings on every line fitting which is either loosened or removed.
c. When tightening line fittings, use two (2) wrenches for equalized support.
d. All fittings and connections must be tightened to the correct torque specification (see torque specifications below).
e. Location and depth of the capillary tube/thermistor probe is extremely important. Refer to the probe location and depth chart attached for proper location.
Evaporator Torque Specifications
Fittings Torque Ft.Lbs.
Evaporator inlet 12
Evaporator outlet 24
Superheat switch for 626 7.25
EXPANSION VALVE:
- Valve to coil 24-29
- Valve to external tube 10-15
- External equalizer connector 10
Probe Location & Depth Chart