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Choke Unloader

NOTE: This adjustment is performed using the choke valve angle gauge. See procedure at beginning of ADJUSTMENTS .
  1. Choke coil lever must be adjusted correctly, and fast idle adjustment must be set before proceeding.
  2. Hold throttle valves wide open. See Fig 1. If engine is warm, close choke valve by pushing up on vacuum break lever tang. Hold in position with a rubber band.
  3. Bubble on choke valve angle gauge should be centered with specified degree mark opposite pointer.
  4. To adjust, bend choke unloader tang on throttle lever until bubble of choke valve angle gauge is centered.
    Fig 1: Adjusting Choke Unloader
    G09337074Courtesy of GENERAL MOTORS COMPANY