DIESEL INJECTION NOZZLE NOZZLES WITH SOFT EDGE FILTERS

DED MAY HAVE MANUFACTURED SOME NOZZLES WITH SOFT EDGE FILTERS THAT LOOSEN AND BREAK UP WITH USE. THIS MAY RESULT IN A PIECE OF MATERIAL INTERMITTENTLY HOLDING THE VALVE OPEN WHICH WILL CAUSE A LOUD ENGINE KNOCK. THE "EDGE FILTER" IS LOCATED IN THE INSIDE OF THE NOZZLE. LOOKING DOWN FROM THE TOP, IT IS RECTANGULAR SHAPED, APPROXIMATELY 3/16 INCH LONG AND 1/8 INCH WIDE. THERE IS DISTANCE BETWEEN THE NOZZLE BODY AND EDGE FILTER TO ALLOW THE FUEL TO PASS. ANY NOZZLE WHICH TESTS SATISFACTORY, BUT HAS A LOOSE "EDGE FILTER" REQUIRES REPLACEMENT OF THE INLET FITTING. THE INLET FITTING SHOULD BE REMOVED AND A NEW INLET FITTING, PART NUMBER 5233668, BE INSTALLED AND TORQUED TO 60 N.M (45 FT. LBS.). A DEEP BROACH SOCKET IS REQUIRED. DO NOT CLAMP NOZZLE IN VISE. THE NOZZLE SHOULD THEN BE TESTED, REFER TO PAGE 6A5-55 OF THE 1981 SERVICE MANUAL. DIESEL EQUIPMENT DIVISION DIESEL INJECTION NOZZLES; DED MAY HAVE MANUFACTURED SOME NOZZLES WITHSOFT EDGE FILTERS THAT LOOSEN AND BREAK UP WITH USE. THIS MAY RESULT IN A PIECE OF MATERIAL INTERMITTENTLY HOLDING THE VALVE OPEN WHICH WILL CAUSE A LOUD ENGINE KNOCK. THE "EDGE FILTER" IS LOCATED IN THE INLET SIDE OF THE NOZZLE. LOOKING DOWN FROM THE TOP IT IS RECTANGULAR SHAPED;APPROXIMATELY 3/16 BODY AND EDGE FILTER TO ALLOW THE FUEL TO PASS. THE NOZZLE SHOULD BE REPLACED IF THE EDGE FILTER IS LOOSE OR HAS MOVED. THE FILTER IS NORMALLY ABOUT 3/16 INCH IN FROM THE INLET. IF IT HAS MOVED, IT WILL BE AT LEAST 5/16 OF AN INCH IN FROM THE END.

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.