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Servo Assembly

CAUTION: If Orange-Yellow lead is shorted to either White-Pink or Grey-Black leads it may be necessary to replace the amplifier.
  1. Disconnect ball chain from throttle linkage. Separate servo-to-amplifier connector. Connect an ohmmeter between Orange-Yellow and Grey-Black wires at servo connector. Resistance should be approximately 85 ohms.
  2. Connect ohmmeter between Orange-Yellow and White-Pink wire leads. Resistance should be approximately 85 ohms. Reconnect ball chain.
  3. Start engine. Jumper Orange-Yellow lead of servo connector to battery positive post and White-Pink lead of servo connector to ground. Momentarily touch Grey-Black lead of servo connector to ground. Servo throttle actuator should tighten bead chain to open throttle. Throttle should hold in that position, or slowly release chain tension. If White-Pink wire is removed from ground, servo should immediately release tension on chain.
    Fig 1: Engine Compartment Speed Control Components For Ford And Mercury Models
    G09347155Courtesy of FORD MOTOR CO.