1977-79 Models
- Remove Brown and Blue line from vacuum control unit. Check for traces of oil. If present, replace unit and oil-filled vacuum lines. Also repair vacuum pump and replace brake booster if oil is found at connecting fitting for vacuum line.
- If no traces of oil are found at control unit or in vacuum lines, start and run engine at idle. Pull off Brown vacuum line from "T" fitting, between vacuum pump and brake booster. See Figure. Check for vacuum. If none present, remove and check "T" fitting and clean with compressed air.
- If vacuum is present, by-pass valve by connecting vacuum control unit directly to "T" fitting. Pump is now free to act directly upon diaphragm of control unit.
- If engine does not shut off immediately, replace vacuum control unit. If engine shuts off immediately, vacuum control unit is not to blame. Problem could be a jammed vacuum valve in steering lock.
- Be sure all vacuum lines are connected properly. See Figure. Start engine, check vacuum control unit, valve in steering lock and injection pump for leaks.NOTE: When installing new unit, be sure control linkage in pump governor is properly engaged and is not holding main rack in full-load position.