DIESEL PUMP CAM RING POSITION AND CAM ADVANCE PIN WEAR

IT HAS BEEN DETERMINED THAT SOME 1981 MODEL DIESEL INJECTION PUMPS WERE MANUFACTURED WITH THE ARROW ON THE CAM RING GOING IN THE WRONG DIRECTION. THOSE DEALERS THAT CHANGE GOVERNOR WEIGHT RETAINER RINGS COULD INSTALL THE CAM RING BACKWARDS BY MATCHING THE ARROW ON THE CAM RING WITH THE ARROW ON THE PUMP HOUSING. PUMPS AFFECTED ARE BETWEEN SERIAL NUMBERS 2797021 THRU 2798039 AND SERIAL NUMBERS 2816298 THRU 2817858. PLACE THE CAM RING ON A TABLE IN THE SAME POSITION AS FIG. 5, (NOTE THE HOLE IN RELATION TO THE TIMING LINE). CHECK TO BE SURE THE ARROW IS POINTING IN THE SAME DIRECTION AS SHOWN IN FIG. 5. DIESEL INJECTION PUMP CAM ADVANCE PIN WEAR: WHEN PERFORMING GOVERNOR WEIGHT RETAINER RING REPAIRS ON 1980, 1981 AND 1982 MODEL DIESEL INJECTION PUMPS, MAKE SURE THAT THE CAM ADVANCE PIN IS INSERTED INTO THE SMALLEST HOLE IN THE CAM RING. FAILURE TO DO SO WILL RESULT IN EXCESSIVE WEAR OF THE BALL ON THE CAM ADVANCE PIN, CAUSING POOR PERFORMANCE, SMOKE AND POOR FUEL ECONOMY. TO DETERMINE WHICH HOLE IS THE SMALLEST, USE A HEAD LOCKING SCREW. THE SCREW WILL ENTER THE LARGE HOLES BUT NOT THE SMALL ONE.

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