Pump Pressure Test

Fig. 1 Connecting Pump Pressure Test Equipment:

1. Disconnect pressure hose from pump and install gauge and shut-off valve C-3309-E and pressure hoses C-4535 using adapters MB990994 and MB991217-A or their equivalents as shown.
2. Bleed power steering system, then start engine and turn steering wheel several times so that fluid temperature rises to approximately 122-140°F.
3. Allow engine to idle at 900-1100 RPM, then completely close shut-off valve.
CAUTION: Do not close shut-off valve for more than 10 seconds, damage to pump may occur.
4. If pressure is not within minimum specifications, repair or replace pump. Refer to Steering and Suspension/Steering/Specifications.
5. Completely open shut-off valve. If pressure is not within minimum specifications, check for clogged or collapsed oil line, or faulty gear box and repair as necessary.
6. With shut-off valve completely open and closed, turn wheels completely right or left. If pressure is not within minimum specifications, valve of gear box is faulty, repair or replace gear box.