1999 Volvo Penta "WT" Models Workshop Manual, Page 317Get this manual
Power Steering System Diagnosis Chart Condition
SYSTEM NOISE: Pump noise "chirp
Possible Cause
Correction
Loose beltLoose belt
Adjust belt tension to specificationAdjust belt tension to specificationNone; slight "hiss" is normal and in no way affects steeri n9
Belt squeal"Hissing" sound
Some noise exists in all power steering systems"Hiss"may be expected
when turning the steering wheel, particularly at low speed
Rattle Rattle or chuckle
Pressure hose touching other parts of powerheadSteering system looseness
Adjust hose position