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Home >> GMC >> 1988 >> Forward Control 6.2 J, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Injection System - Diesel >> Adjustments >> Injection Pump Timing
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Injection Pump Timing

  1. Check alignment of injection pump timing marks on top of engine front cover and injection pump flange (half circles on California models and scribe marks on Federal models).
  2. If timing marks are not aligned, loosen 3 retaining nuts, and align mark on injection pump with mark on front cover. Tighten nuts to 30 ft. lbs. (41 N.m) and adjust throttle linkage.
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