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Pump Pressure Test

  1. Install a pressure gauge with shut off valve in series with the pressure hose. Start the engine and set idle between 600-700 RPM. Check that fluid temperature in the reservoir is maintained between 122°-140°F (50-60°C).
  2. Close pressure gauge shut off valve and check a that pressure is between 782-896 psi (55-63 kg/cm2 ). If pressure is less than specifications, check for faulty pump or a sticking flow control valve.
  3. Open shut off valve. Pressure should drop at least 71 psi (5 kg/cm2 ). If pressure drops more than this, check for bent or kinked lines or contaminated fluid.
  4. With shut off valve open, turn steering wheel to full lock position, then release. If pressure drops more than 71 psi (5 kg/cm2 ), check for faulty valve in steering gear.
  5. Turn steering wheel to full right and full left lock position. If pressure drops more than 71 psi (5 kg/cm2 ) with shut off valve open, look for excessive internal leakage in the power steering gear, caused by excessive valve clearances or broken seals.
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