Paint: Service Precautions

Handling of Refrigerant Lines and Fittings

Important: Before opening the refrigeration system, ensure that the work area is well-ventilated. Do not conduct welding or steam-cleaning operations on or near the following areas:


* The refrigeration system lines

* Other air conditioning parts on the vehicle


* Ensure that all of the metal tubing lines are free of dents or kinks that may cause line restriction. Line restriction may cause the loss of system capacity.
* Do not bend the flexible hose lines to a radius of less than 4 times the diameter of the hose.
* Do not allow the flexible hose lines to come within 65 mm (2.5 in) of the exhaust manifold.
* Regularly inspect the flexible hose lines for leaks or brittleness. Replace the lines with new lines if deterioration or leaking is found.
* When disconnecting any fitting in the refrigerant system, recover the system of all Refrigerant 134a. Use the following procedure in order to recover the system of all Refrigerant 134a :

1. Proceed very cautiously regardless of the gage readings.
2. Open the fitting very slowly.
3. Keep hands and face away from the fitting in order to prevent injury.
4. If pressure is noticed when a fitting is loosened, allow the pressure to bleed off slowly.
5. Immediately cap refrigerant lines that are opened to the atmosphere. This action prevents the entrance of moisture and dirt. Dirt and moisture can cause internal A/C compressor wear or plugged lines in the following areas:

* The condenser
* The expansion (orifice) tubes
* The compressor inlet screens
* The evaporator core

6. Remove the sealing caps from subassemblies just before making the connections for final assembly. Apply a small amount of clean 525 viscosity refrigerant oil on all of the tubes and hose joints.




* Use new O-ring seals dipped in 525 viscosity oil when assembling joints. The oil aids in assembly and helps provide a leakproof joint. The O-ring seals and seats must be in perfect condition because a burr or a piece of dirt can cause a refrigerant leak.
* Use the proper wrenches in order to make connections on the O-ring seal fittings.



Using improper wrenches may damage the connection. Use a wrench in order to back up the opposing fitting in order to prevent distortion of the connecting lines or the components.
* Use three different wrenches in order to simultaneously hold the following parts when connecting the flexible hose connections:

- The swagged fitting
- The flare nut
- The coupling that is attached to the flare nut
This action prevents turning in the fitting and damage to the seat.

* Tighten tubing connections to the specified torque. Refer to Fastener Tightening Specifications Fastener Tightening Specifications.