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Pressure & Flow Rate Test

    CAUTION: To prevent power steering pump damage during pump pressure testing, open valve on tester before starting engine. During testing, DO NOT turn steering wheel unless specified in procedure.
  1. Disconnect high pressure line at power steering pump. Connect Power Steering System Tester (SA9134C) between power steering high pressure line and pump fitting. Set parking brake. Place transmission in Park (Neutral on manual transmission). Open valve on tester. Start engine. Allow power steering system to reach operating temperature (2-3 minutes). Ensure fluid level is correct. If necessary, bleed hydraulic system. See HYDRAULIC SYSTEM BLEEDING  under LUBRICATION.
  2. With engine idling, record power steering pressure and flow rate. If pressure is greater than 150 psi (10.5 kg/cm2 ), stop engine and check for restricted power steering hose.
  3. Partially close valve until pressure is 700 psi (49 kg/cm2 ). Record flow rate. If difference between this flow rate and that obtained in previous step is greater than one gallon (3.8L) per minute, replace power steering pump ring, rotor and vanes. Check for worn or damaged pressure plate and thrust plates. Replace components, as necessary, or entire pump assembly.
    4. CAUTION: Pump will be damaged if tester valve is held closed for more than 5 seconds.
  4. Completely close valve for a few seconds, and then open it. Do this 3 times, recording highest pressure obtained each time valve is closed. If readings are not within 50 psi (3.5 kg/cm2 ) of each other, replace flow control valve. See Figure . Ensure flow control valve moves freely in bore.
  5. With engine speed at 1600 RPM, record flow rate. If difference between this flow rate and that obtained in step  2 is less than one gallon (3.8L) per minute, go to next step. If difference between flow rates is greater than one gallon (3.8L) per minute, remove and clean flow control valve. DO NOT disassemble valve. Ensure valve moves freely.
  6. Turn steering wheel from stop to stop, recording pressure and flow rate at each stop. DO NOT hold steering wheel at stops for more than 5 seconds. If flow rate at either stop is greater than one gallon (3.8L) per minute, steering gear is leaking internally. Replace steering gear. Remove tester. Fill and bleed system. See HYDRAULIC SYSTEM BLEEDING  under LUBRICATION.
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