TROUBLESHOOTING 999 SERVICE/MAINTENANCE MANUAL
10-52
Published 05-16-17, Control # 233-03
Test 20 – Setting Pump Neutral
To set pump neutral:
• Engine must be off and power on, with all brakes and
locks engaged.
• Disconnect the PC from the pump EDC by removing the
cable at the EDC.
• Install a 0 – 600 psi (0 – 42 bar) gauge at each servo
gauge port.
• Start engine with all brakes and locks engaged.
• Loosen the hex lock nut and rotate the neutral adjusting
screw with hex wrench until pressure increases in one of
the gauges.
• Note the handle position of the hex wrench and without
moving wrench, rotate the neutral adjusting screw
counter-clockwise until pressure increases in the other
gauge.
• Note the handle position of the hex wrench again and
without moving wrench, rotate the neutral adjusting
screw clockwise halfway between the last position.
• The control should now be in neutral with both gauges
reading the same case pressure.
• Hold the neutral adjusting screw with the hex wrench
and tighten the lock nut.
• Remove the gauges and install the servo gauge port
plugs.
Wrench Sizes
Item Description
1 Neutral Adjusting Screw and Lock Nut
2 Servo Gauge Ports
Locking Nut Hex Wrench
Early Series Units 17 mm 5 mm
Current Series Units 13 mm 4 mm