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Forward Delay Valve

  1. Connect an external vacuum source to port on black (or red) side of delay valve. Connect one end of a 24" section of rubber hose to vacuum gauge and the other end to the port on colored side of valve.
  2. With elapsed time device in view and a constant 10 in. Hg of vacuum applied, note time required for gauge pointer to move from 0 in. Hg to 8 in. Hg.
  3. If valve fails to meet time limits, replace valve. If valve meets specifications, install so that black (or red) side is toward vacuum source.
Forward Delay Valve Time Limits(1)

Valve Color Min. Time Max. Time
Black/Purple 0.3 0.7
Black/Gray 0.6 1.6
Black/Brown 1.0 3.0
Red/Blue 1.9 5.7
Black/White 2.7 9.3
Black/Yellow 4.5 13.2
Black/Green 14.0 47.2
(1) Time in seconds.