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Bellows Comparison Check

  1. Using Comparison Gauge (J-24466), compare load of vacuum modulator with known good modulator of same type. Part number is stamped on modulator dome. Install good modulator on either end of gauge.
  2. Install modulator in question on opposite end of gauge. Holding modulators in horizontal position, bring them slowly together under pressure. If modulator in question is bad, gauge line will remain Blue. If modulator in question is good, gauge line will be White.
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