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Time Delay Test

  1. Discharge system completely by bleeding air at bleed valve on compressor. Disconnect link and hold height control valve lever down to exhaust air sleeve shocks. Disconnect lines at intake and exhaust ports of height control valve. Connect external air source to inlet port and apply 90 psi. Move valve lever one inch down from neutral position. Quickly move valve lever upward two inches. The delay before air starts to escape should be 4-30 seconds.
  2. Connect external air source to exhaust port and apply 90 psi. Move valve up one inch from neutral position. Quickly move valve lever down two inches. Delay before air starts to escape should be 4-30 seconds.
  3. If either delay is not within specifications, there has been either a loss of silicone fluid from height control valve or valve has lost its internal adjustment due to damage or wear. Replace valve in either case.
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