FixVault

Vacuum Break

  1. Place cam follower on HIGHEST step of fast idle cam. Use outside vacuum source and apply enough vacuum to seat diaphragm. See Fig 1.
  2. Diaphragm plunger should be IN and seated. If used, bucking spring should be fully compressed.
  3. Push up on choke coil lever. Rod should be snug in end of diaphragm plunger slot. On models equipped with delay feature, cover purge bleed hole in vacuum break end cover with masking tape.
    Fig 1: Adjusting Vacuum Break
    G09341275Courtesy of GENERAL MOTORS COMPANY
  4. Measure specified clearance between lower edge of choke valve and air horn wall. Measurement can be made with a specified drill or pin gauge.
  5. To adjust, bend "U" shaped portion of vacuum diaphragm connector link. Remove masking tape. Check linkage for binding.
Fig 2: Exploded View of 1ME Carburetor
G09341276Courtesy of GENERAL MOTORS COMPANY
Fig 3: Adjusting Choke Unloader
G09341277Courtesy of GENERAL MOTORS COMPANY