Modulator Assembly: Inspection
- Inspect vacuum modulator valve for scoring, nicks or burrs.
- Inspect "O" ring seal for nicks or cuts.
- Inspect vacuum modulator for bent neck or dented can.
- Install hand-held vacuum pump to modulator and apply 18 in. hg. (15 kPa).
- Install Comparison Gauge (J-23738-A) onto modulator and a known good modulator of the same type. See Fig 1 .
- Apply pressure to both. If indicator line moves out of view, modulator must be replaced.