Frequency Valve: Service and Repair

1. Remove injection pump, then remove mounting bracket from pump.
2. Remove pulse valve mounting screws, then withdraw pulse valve from pump.
3. Remove small pulse valve O-ring from pump.
4. Lubricate O-rings with fuel, then install large O-ring on pulse valve and fit small O-ring in pump cavity.
5. Install pulse valve and torque screws to 14 ft. lbs.