Fluorescent Leak Detectors - R-134a

R134A LEAK DETECTION WITH TRACER DYE
A fluorescent leak tracer dye Kent-Moore P/N J 41447, mixes with the R134a Polyalkylene glycol (PAG) oil. This dye is detectable through the use of an ultraviolet (black) light and glows yellow/green at the leak location (similar to using dye in engine leak detection). J 41447 is the only approved dye by General Motors. Not all R134a dyes are compatible with GM's PAG oil. Some dyes decrease the oil viscosity or chemically react with the oil. Use of alternate products may affect system reliability and cause premature compressor failure.

CAUTION: This dye is not to be used in R-12 systems.

TECHNICIAN SHOULD KEEP IN MIND
1. PAG oil is water soluble and traces of PAG oil found at leaking joints are subject to "washing out". Condensation on refrigerant lines or the evaporator core may wash the PAG oil and leak dye off the line or off the core and out the condensate drain. This can make some leaks harder to find using the dye detector. Fluorescence at the drain opening would indicate a core leak.
2. Use of the R134a tracer dye requires time. Depending upon the leak rate, it may take between 15 minutes and 7 days for the leak to become visible.
3. The dye, mixed with the PAG oil, is retained in the system and is detectable for 2+ years. Do not double or triple charge the system with dye as this may cause reliability concerns. Use only the 1/4 oz. charge.

The dye has a refrigerant leak detection notice sticker included with the package. Complete the sticker information and place near the charge label.

DYE INJECTION R-134A DYE CAN BE INJECTED TWO WAYS
1. With the A/C system charged, use the instructions provided with the new R134a leak dye injection tool, J 41436.
2. With A/C system discharged, add dye into the newly replaced component assembly.

NORMAL TO FIND OIL TRACES
It is important to note that it is normal to find oil traces at the compressor shaft seal during compressor operation, some oil will hydraulically seep past the shaft seal. This does not mean that the shaft seal is defective or that the refrigerant has leaked. Refrigerant leaks at the shaft seal should be verified with the electronic leak detector (J 39400) following the procedure detailed in the Service Manual. If, however, the amount of oil is excessive, the shaft seal is suspect and should be replaced. (For example, refrigerant oil has coated the clutch plate edge at gap between clutch and pulley, or oil slinging has occurred-oil line shows on underside of hood, etc.).

Also, after working on A/C components with dye, it is important to wipe the joint and/or access ports clean of any residual dye with GM solvent (GM P/N 1050436) or equivalent to prevent false diagnosis at a later point.