Hydraulic System Pressure Test

Connect a pressure gauge/valve between steering pump and steering gear. See Fig 2 . Bleed any air from system. Open valve. Start engine and let idle.
Turn steering wheel lock-to-lock to increase fluid temperature. To measure pump fluid pressure, completely close the gauge valve for 15 seconds and increase engine speed to 1000-1500 RPM.
Pump pressure should be at least 1138 psi. (78 kg/cm² ). If pump pressure is not to specification, pump overhaul is necessary.
CAUTION: Leaving gauge valve closed for more than 15 seconds can damage the pump.
To measure steering gear fluid pressure, open the gauge valve completely. Increase engine speed to 1000-1500 RPM. Turn steering wheel from lock-to-lock.
Do not keep steering wheel fully turned for more than 10 seconds. The correct gear housing fluid pressure limit is 924 psi (64 kg/cm² ) at a temperature of 122-140°F (50-60°C).
If less than specification, steering gear is defective. If the pump is defective, replace as a complete assembly.

Fig 1: Exploded View of 323 Rack & Pinion Steering Gear

Courtesy of MAZDA MOTORS CORP.

Fig 2: Pressure Gauge Test Set Up Place gauge set valve on gear housing side. Courtesy of Mazda Motors Corp.