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Valve Air Flow Check

  1. Attach a 9.75-10.25"3 vacuum tank to colored side of valve.
  2. Expose Black side to atmospheric pressure.
  3. Observe vacuum drop. Time required for vacuum to drop from minus 20 In Hg to minus 2 In Hg should be .5 second maximum.
  4. To check vacuum recovery air flow, attach a 22.25-23.25 In3 vacuum tank to Black side of valve.
  5. Expose colored side to atmospheric pressure.
  6. Observe vacuum drop. Time required for vacuum to drop from 16 In Hg to 8 In Hg will be 4-6 minutes. If delay valve does not comply with any of test results, replace unit.
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