Expansion Valve: Service and Repair

Fig. 10 Exploded view of evaporator core assembly.:

EVAPORATOR CORE AND / OR EXPANSION VALVE
1. Disconnect battery ground cable and discharge A/C system.
2. Disconnect refrigerant lines and vacuum hose at firewall connections, then plug open lines and fittings.
3. Remove instrument panel, refer to HEATER CORE.
4. Disconnect wiring harness connector to thermostatic switch.
5. Disconnect vacuum hose to evaporator case at T-fitting and disconnect wiring harness connector to relay.
6. Remove three evaporator case retaining nuts, then remove case assembly.
7. Carefully remove foam insulation from evaporator case inlet and outlet, Fig. 10.
8. Remove clips securing evaporator case and remove upper case half, carefully removing thermostatic switch sensor from evaporator core.
9. Remove evaporator with expansion valve from lower case.
10. Remove expansion valve capillary bulb from evaporator.
11. Disconnect expansion valve and equalizer tube from evaporator, then remove valve. If evaporator is to be replaced, add 1.7 oz. of refrigerant oil to new evaporator.
12. Reverse procedure to install, noting the following:
a. Ensure thermostatic switch sensor and expansion valve capillary bulb are properly installed and insulated.
b. Evacuate and recharge system, then check for leaks.