Steering System - Power: Overview Isuzu Trooper II

DESCRIPTION & OPERATION

The power-assisted recirculating ball steering system consists of power steering gear assembly, hydraulic pump and hydraulic lines. Oil pump and fluid reservoir are remotely mounted.

On all models, power steering gear is an integral type, consisting of conventional ball/screw-type steering gear. The gear unit combines with a rotary and torsion bar-type control valve and power cylinder. The belt-driven oil pump is a constant-delivery, vane-type.

Scheme 1

1. With engine off, disconnect pressure hose from pump. Install power steering pressure gauge and shutoff valve between pump and steering gear unit. Gauge must be between pump and shutoff valve. (Scheme 1) Bleed power steering system. See HYDRAULIC SYSTEM BLEEDING under LUBRICATION. CAUTION: DO NOT hold steering wheel at full-lock position for more than 5 seconds. Internal pump damage will result.
2. Ensure pressure gauge shutoff valve is open. Start engine and let idle for at least 2 minutes. Check fluid level in reservoir and refill if needed. Turn steering wheel from lock-to-lock several times until fluid has reached normal operating temperature. Have another technician hold steering wheel at full-lock position for less than 5 seconds. CAUTION: DO NOT close shutoff valve for more than 5 seconds. Severe pump damage will result.
3. Record pressure reading. If fluid pressure is greater than specified, a restriction is present or pump may be faulty. See «POWER STEERING PRESSURE SPECIFICATIONS»(ref-123455-S05483504122001092500000) table. If fluid pressure is less than specified, return front wheels to straight-ahead position. Increase and hold engine speed at 1500 RPM. Close and open pressure gauge shutoff valve 3 times.
4. Check and record highest pressure gauge readings. If pressure reading is within specification, steering gear box is faulty. If reading is less than specified, pump is faulty.

POWER STEERING PRESSURE SPECIFICATIONS