ROUGH ENGINE OPERATION 50MPH DISTRIBUTOR WAVE WASHER

IF A CUSTOMER DESCRIBES A ROUGH ENGINE OPERATION OR POOR DRIVEABILITY AT SPEEDS OF APPROXIMATELY 80 KPH, THE WAVE WASHER INSTALLED ON THE MAINSHAFT OF THE H.E.I. DISTRIBUTOR COULD BE THE CAUSE. SEE FIGURE 1. THERE ARE THREE (3) CHECKS THAT WILL VERIFY IF THE WAVE WASHER IS AT FAULT: 1.A SCOPE PATTERN AT APPROXIMATELY 1800-2000 ERPM WILL BE ERRATIC AND SOMETIMES WILL SHOW AS HIGH AS TEN (10) IGNITION PULSES (FIRING CYLINDERS). 2.TIMING WILL RETARD TO A -10 DEGREES AT APPROXIMATELY 1800 ERPM. 3.IF USING THE ALCL (ASSEMBLY LINE COMMUNICATIONS LINK) - SCAN TOOL, AN RPM READING WILL SHOW 5000 ERPM WHEN ACTUALLY THE ENGINE IS ONLY RUNNING AT APPROXIMATELY 1800 ERPM. THE DISTRIBUTOR BUILD CODES WHEN THIS POTENTIAL WAVE WASHER CONDITION COULD OCCUR ARE 1A06 THRU 1D29. SEE FIGURE 1. DO NOT REMOVE OR INSTALL A WAVE WASHER UNLESS THE H.E.I. DISTRIBUTOR FALLS WITHIN THESE DAY BUILD CODES. AFTER THESE CHECKS HAVE BEEN MADE AND THE CONDITION HAS BEEN VERIFIED, A NEW WAVE WASHER CAN BE ORDERED USING PART NUMBER 1984360.

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