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Accelerating Pump Rod Adjustment

NOTE: This is a linkage adjustment and not a seasonal setting.

Back out slow idle speed (and fast idle speed) screws until throttle valves are completely closed. Make sure pump rod is connected in proper hole of arm as indicated in specification table. Hold throttle valves in closed position and use a gauge or scale to check pump adjustment.

NOTE: If a gauge is used, place it on top of air horn next to pump plunger. End of pump shaft should slide freely into hole in gauge marked "Pump".

If a scale is used, measure distance from top of air horn casting to bottom of pump plunger shaft (see Specifications ). If height not correct, adjust by bending pump rod.

Fig 1: ACCELERATING PUMP ROD ADJUSTMENT
G09353183Courtesy of GENERAL MOTORS COMPANY