R134A LEAK DETECTION WITH TRACER DYE. Geo Storm 1993

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SUBJECT: R134A LEAK DETECTION WITH TRACER DYE

MODELS: ALL 1993-1995 VEHICLES WITH OEM R134A SYSTEMS ALL R12 VEHICLES RETROFITTED TO R134A SYSTEMS

R134A REFRIGERANT IS UNIQUELY DIFFERENT FROM R12 REFRIGERANT AND REQUIRES SOME CHANGES IN THE REPAIR METHODS, TOOLS AND MATERIALS USED IN A/C SERVICE. TWO IMPORTANT DIFFERENCES BETWEEN R134A AND R12 WHICH AFFECT THE TECHNICIANS ABILITY TO LOCATE REFRIGERANT LEAKS ARE:

1. THE R134A MOLECULE IS SMALLER THAN THE R12 MOLECULE AND THEREFORE WILL LEAK THROUGH SMALLER OPENINGS. FOR THE SAME SIZE OPENING THE SMALLER R134A MOLECULE WILL LEAK OUT FASTER THAN THE R12.

2. R134A REFRIGERANT DOES NOT CONTAIN CHLORINE WHICH THE OLDER R12 ELECTRONIC LEAK DETECTORS FOUND VERY EASY TO IDENTIFY. MANY OF TODAY'S ELECTRONIC LEAK DETECTORS HAVE DIFFICULTY LOCATING SMALL R134A REFRIGERANT LEAKS.

IN ORDER TO INSURE THE HIGHEST QUALITY IN A/C SYSTEM SERVICE, THE J39400 ELECTRONIC LEAK DETECTOR WAS RELEASED AS AN ESSENTIAL TOOL FOR ALL GM DEALERS. THIS IS THE ONLY REFRIGERANT LEAK DETECTOR APPROVED BY GM FOR SERVICE ON R134A VEHICLES. IF MAINTAINED PROPERLY (REFERENCE BULLETIN NO. 431218) AND USED IN ACCORDANCE WITH SERVICE MANUAL PROCEDURES, THE J39400 WILL PROVIDE THE MOST ACCURATE AND EFFICIENT METHOD OF LOCATING R134A REFRIGERANT LEAKS UNDER MOST CONDITIONS.

IF THE TECHNICIAN CANNOT FIND THE LEAK WITH THE J39400 AND THE SYSTEM IS KNOWN TO HAVE LOST CHARGE, A NEW FLUORESCENT LEAK TRACER DYE KENT-MOORE* P/N J41447, HAS BEEN RELEASED THAT MIXES WITH THE R134A 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). **J41447 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.

NOTE: THIS DYE IS NOT TO BE USED IN R-12 SYSTEMS.

UNLIKE MINERAL OIL, THE R134A PAG OIL HAS SPECIAL PROPERTIES THE 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 INDICATES 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, J41436.

2. WITH A/C SYSTEM DISCHARGED, ADD DYE INTO THE NEW REPLACED COMPONENT ASSEMBLY.

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 (J39400) 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) TO PREVENT FALSE DIAGNOSIS AT A LATER POINT.

*WE BELIEVE THIS SOURCE AND THEIR EQUIPMENT TO BE RELIABLE. THERE MAY BE ADDITIONAL MANUFACTURERS OF SUCH EQUIPMENT. GENERAL MOTORS DOES NOT ENDORSE, INDICATE ANY PREFERENCE FOR OR ASSUME ANY RESPONSIBILITY FOR THE PRODUCTS OR EQUIPMENT FROM THESE FIRMS OR FOR ANY SUCH ITEMS WHICH MAY BE AVAILABLE FROM OTHER SOURCES.

PART AVAILABILITY:

GM SOLVENT, P/N 1050436, IS CURRENTLY AVAILABLE FROM GMSPO.

FIGURES: 0

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER". THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS THAT MAY OCCUR ON SOME VEHICLES, OR TO PROVIDE INFORMATION THAT COULD ASSIST IN THE PROPER SERVICE OF A VEHICLE. PROPERLY TRAINED TECHNICIANS HAVE THE EQUIPMENT, TOOLS, SAFETY INSTRUCTIONS AND KNOW-HOW TO DO A JOB PROPERLY AND SAFELY. IF A CONDITION IS DESCRIBED, DO NOT ASSUME THAT THE BULLETIN APPLIES TO YOUR VEHICLE, OR THAT YOUR VEHICLE WILL HAVE THAT CONDITION. SEE A GENERAL MOTORS DEALER SERVICING YOUR BRAND OF GENERAL MOTORS VEHICLE FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.