TRUCK SERVICE MANUAL TM 5-4210-230-14&P-1 BODIES AND CABS 10. Install  dash  panel  seals  and  retainers  surrounding evaporator inlet and outlet tubes. 11. Evacuate   and   charge   air   conditioning   system   as outlined under SERVICE OPERATIONS. 12. Install covers on heater/evaporator unit and instrument panel. 13. Lower hood and fender assembly. EXPANSION VALVE Removal: 1. Make sure key switch is "OFF". 2. Raise hood and fender assembly. 3. Discharge  air  conditioning  system  as  outlined  under SERVICE OPERATIONS. 4. Remove cover from right side of instrument panel. 5. Remove cover from heater/evaporator unit. 6. Disconnect   wiring   harness   connector   from   blower resistor located on bottom of blower housing. 7. Remove  insulated  tape  from  expansion  valve  and evaporator inlet and outlet tubes. 8. Disconnect expansion valve equalizer line from fitting on evaporator outlet tube (Fig. 49). 9. Remove  screw  and  clamp  securing  expansion  valve feeler bulb to evaporator outlet tube. 10. Disconnect expansion valve inlet tube from expansion valve. 11. Remove   bolt,   nut   and   clamp   securing   expansion valve to bracket on blower housing. 12. Using   two   wrenches,   disconnect   expansion   valve from evaporator core inlet tube.  Remove expansion valve. Installation: 1. Lubricate   threads   with   refrigerant   oil   and   connect expansion    valve    to    evaporator    core    inlet    tube. Tighten fitting using two wrenches. 2. Install clamp, bolt and nut' securing expansion valve to bracket on blower housing. 3. Lubricate   threads   with   refrigerant   oil   and   connect expansion    valve    inlet    tube    to    expansion    valve. Tighten nut to 11-14 N.m (15-20 ft.lbs.). Fig. 49  Removing Expansion Valve 4. Position  expansion  valve  feeler  bulb  on  evaporator core outlet tube and secure with clamp and screw. 5. Lubricate   threads   with   refrigerant   oil   and   connect expansion valve equalizer line to fitting in evaporator outlet tube.  Using two wrenches tighten fittings to 7- 11 N.m (10-15 ft. lbs.) torque. 6. Wrap expansion valve and evaporator inlet and outlet tubes with insulated tape. 7. Connect wiring harness connector to blower resistor. 8. Evacuate   and   charge   air   conditioning   system   as outlined under SERVICE OPERATIONS. 9. Install covers on heater/evaporator unit and instrument panel. 10. Lower hood andfender assembly. FAN DRIVE OVERRIDE SWITCH The fan drive override switch can be replaced without discharging  the  refrigerant  from  the  air  conditioning  system. A  spring-loaded  valve  in  the  compressor  discharge  service port prevents loss of refrigerant when switch is removed. Removal: 1. Raise hood and fender assembly. 2. Make sure key switch is '"OFF". 3. Disconnect   fan   drive   override   switch   wires   from engine wiring harness. CTS-2731  Page 33 PRINTED IN UNITED STATES OF AMERICA