Distributor Vacuum Control Valve Adjustment

Move dashpot so that stem does not contact throttle. Connect tachometer, vacuum gauge (0-30 in. Hg), and remove distributor vacuum tube at distributor and clamp tube closed. Set timing and hot (slow) idle to specifications. Reconnect vacuum tube and run engine at 2000 RPM for five seconds in Neutral. When throttle is released, distributor vacuum should increase to over 16 in. Hg for a minimum of one second and fall below six in. Hg within three seconds. Remove vacuum control cover and turn adjusting screw for adjustment. Readjust dashpot. See Dashpot Adjustment  . Recheck valve performance. If distributor vacuum does not fall below six in. Hg within four seconds after throttle is released, readjust or replace dashpot.