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Function Testing

  1. Disconnect overtravel lever from link. Exhaust air from shocks by holding lever down until air sleeves deflate. Start engine and run at idle. Pressurize system with external source to 90 psi. Hold lever down in exhaust position until sleeves deflate. If sleeves do not deflate, remove exhaust adaptor from control valve and hold lever down to deflate sleeves. If sleeves now deflate, replace adaptor, "O" ring, and filter. If defective condition is not corrected by these replacements, replace height control valve.
  2. Hold lever up in intake position until sleeves inflate. If sleeves inflate and hold, proceed to TIME DELAY TEST . If sleeves inflate, then leak down, check lines, fittings, and sleeves for air leaks. If sleeves still do not inflate, perform LEAK TEST .
    Fig 1: Automatic Air Leveling System
    G09349120Courtesy of FORD MOTOR CO.