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Hydraulic System Pressure Test

  1. Ensure belt tension is correct. Disconnect high pressure line from power steering pump. Connect Power Steering Pressure Gauge (J-5176-D) hose to power steering pump fitting. Connect other hose from valve side of tester to steering gear inlet.
  2. Open valve on pressure gauge. Check fluid level and add fluid as necessary. Check for possible leaks at pressure gauge connections. Bleed air from system. See HYDRAULIC SYSTEM BLEEDING  under LUBRICATION. Run engine until fluid reaches normal operating temperature of 150-170°F (66-77°C). Check fluid level and add fluid as necessary.
  3. Note pressure reading with valve open and engine idling. Pressure should be 80-125 psi (6-9 kg/cm2 ). If pressure exceeds 200 psi (14 kg/cm2 ), check hoses for restrictions and poppet valve for proper assembly.
    CAUTION: To prevent pump damage, DO NOT hold gauge valve closed for more than 5 seconds.
  4. Completely close and open valve 3 times. Record highest reading each time. Readings should be within specification. See PRESSURE TEST SPECIFICATIONS  table.
  5. If pressure readings are within specification and within 50 psi (4 kg/cm2 ) of each other, pump is operating properly.
  6. If readings are within specification but not within 50 psi (4 kg/cm2 ) of each other, flow control valve in pump is sticking. Remove valve, but DO NOT disassemble it. Clean valve. Flush system if dirty.
  7. If pressure is constant but more than 100 psi (7 kg/cm2 ) below specification, clean or replace flow control valve in pump. If readings are still low, replace pump.
  8. If pressure readings are as specified, turn steering wheel from stop to stop with valve open. Record highest pressure with wheels at both stops. If highest pressure is not equal to highest pressure recorded in step 2), steering gear is leaking internally. Repair or replace assembly.
  9. Turn engine off. Remove tester. Reconnect pressure hose. Check fluid level. Bleed hydraulic system. See HYDRAULIC SYSTEM BLEEDING  under LUBRICATION.
PRESSURE TEST SPECIFICATIONS

Idle Pressure psi (kg/cm2 ) Relief Pressure psi (kg/cm2 )
80-125 (6-9) 1250-1450 (87-102)
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