Hydraulic System Pressure Test

NOTE: Fluid temperature should be at least 176°F (80°C) before testing.

Disconnect pressure lines from steering gear and pump. Install Pressure Gauge (SST 09631-22020 ) with gauge side connected to pump and valve side of gauge to pressure line. See Fig 1.
Bleed air from system. See HYDRAULIC SYSTEM BLEEDING in this article. Ensure fluid level is correct. Start engine and allow to idle. Close valve and note pressure reading. Open valve.
CAUTION: DO NOT close valve for more than 10 seconds.

Fig 1: Installing Pressure Gauge
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Pressure should be at least 1067 psi (75 kg/cm² ). Replace power steering pump if pressure is low.
With valve open, record pressure with engine speed at 1000 and 3000 RPM. Difference between both reading should not exceed 71 psi (4.9 kg/cm² ). Replace flow control valve in power steering pump if difference exceeds specification.
Turn wheels against lock and note pressure reading with valve open. Pressure should be at least 1067 psi (75 kg/cm² ). If pressure is low, steering gear has internal leakage and must be repaired.