1999 Volvo Penta "WT" Models Workshop Manual, Page 320Get this manual
Pump Leakage
1An over-filled pump reservoir can cause le8kThe fluid in the steering system expands as it heats up during normal usage and fluid level rises in reservoirExcess fluid is forced through the breather cap hole where it may be sprayed over the engine by the drive belt
2Remove filler cap from pump reservoir and check fluid levelFill pump reservoir to full mark on dipstickStart engine, momentarily hold steering wheel against stop, and check connections at tool for leakage3Bleed system as outlined under Purging Air From Steering System4Insert Kent-Moore Thermometer Tool, J-5421 into reservoir filler openingStart the engine and move steering wheel from stop-to-stop several times until thermometer indicates that hydraulic fluid has reached its normal operating temperature of approximately 150 to 190 (65 to 88 C)0 0IT] IT] IT]