77 Newport AC Troubleshooting

[Blake Ludvigson]

System is holding pressure, passed the leak test, clutch kicks in, blows warm air still. Any ideas before I waste $40 of refrigerant and take it apart. Rv2 OEM system

 

[commando1]

Manual air or AutoTemp II?

 

[75LandYacht]

Bad expansion valve maybe..

 

[Davea Lux]

You need to attach a service manifold to see if the refrigerant is at proper operating pressures. Put your hand on the back side of the expansion valve, it should be cold to the touch, that will tell you if it is working. If this is an Auto Temp system, the controls might be messed up to where the heater air door is open and blowing hot air to defeat the A/C function. Start by checking the operating pressures. If the system was discharged for a long time, the expansion valve might also be stuck, try tapping the head of the valve lightly with a block of wood, being careful not to damage the capillary on the valve. If the system was discharged for a long time, the filter dryer might be bad also, this can cause the expansion valve to work briefly and then ice up and stick. If the system was not properly converted from R-12 to R-134a there might also be a big glob of jellied oil blocking the expansion valve. There are lots of possibilities here.

Dave

 

[Blake Ludvigson]

Manual air or AutoTemp II?

Manuly air