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Hydraulic Pressure Tests

  1. Check for hydraulic leaks in system. Check power steering pump does not exhibit sustained failure or internal damage that may contaminate fluid in system. If there is a possibility of burned fluid or metal particles in fluid, brake system should be purged before connecting power steering analyzer.
  2. Connect Power Steering System Analyzer (014-00230). Follow installation procedure supplied with analyzer. Fully open shutoff valve, start engine and purge air from brake system by applying brakes several times. Shut off engine and check connections for leaks.
  3. Check for proper fluid level at reservoir and add or remove fluid as required. Recheck for air in system by restarting engine, partially closing shutoff valve and viewing pressure gauge. If gauge needle vibration is excessive, too much air remains in system. Install thermometer in reservoir and connect tachometer to engine.
  4. Fully open analyzer shutoff valve. Start engine and run at 2000 RPM. When fluid temperature reaches 130°F (55°C), record flow and pressure. If flow is less than 3.1 gal/min (11.7 L/min), check to see if correct pump is installed. If correct pump is installed, continue testing. If pressure exceeds 25 psi (1.8 kg/cm2 ), check lines for kinks or obstructions.
  5. Check pump for minimum efficiency flow. Decrease engine speed to 750-850 RPM. Slowly close shutoff valve to build pressure to 1200 psi (84 kg/cm2 ). Record flow with temperature at least 130°F (55°C). If flow is less than 1.3 gal/min (5 L/min), check if correct pump is installed. Pump may require repair or replacement, especially if flow in step  4 was also less than value indicated.
  6. Check pump for pressure relief valve operation. Run engine at 750-850 RPM. Completely close and partially open shutoff valve 3 times. Read pressure when valve is fully closed. If pressure is less than 1230 psi (84.8 kg/cm2 ), or greater than 1350 psi (93 kg/cm2 ), clean or replace pressure relief valve. If pressure is within specification, pump is operating normally and other areas should be investigated.
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