Oil Pump Relief Pressure Inspection

The following procedures require the use of oil pressure gauge assembly tool No. MB990662, or equivalent, power steering oil pressure gauge pump side adapter tool No. MB990993-01 and power steering oil pressure gauge hose side adapter tool No. MB990994-01, or equivalent.

Fig. 5 Pressure Gauge Installation:

1. Disconnect pressure hose from oil pump, then connect special tools as shown, Fig. 5.
2. Bleed air from system, then turn steering wheel from stop to stop until fluid temperature in reservoir is 122-140°F.
3. Start engine and run at 900-1100 RPM.
4. Fully close shutoff valve and ensure oil pump relief pressure is as specified in "Power Steering Pressure Specifications" chart. Do not leave shutoff valve closed for more than ten seconds, as damage or injury may occur.
5. If pressure is not within specified range, service oil pump as outlined under "Power Steering System Service".
6. Remove special tools and bleed system.