TM-9-2320-280-20 HMMWV Technical Manual Unit Maintenance Volume 1 Download
Page 573 of 890
TM 9-2320-280-20-1 REFERENCE INFORMATION STEERING SYSTEM 8. Loosen hose clamp and remove control valve return hose from tube on power steering pump. 9. Plug return hose with plug or bolt (3/8 in. or 10 mm dia.) and secure with hose clamp. 10. Connect other end of bypass hose to tube on power steering pump and secure with hose clamp. 11. Connect STE/ICE-R to vehicle diagnostic connector and set for measuring RPM (para. 2-43). 12. Open analyzer valve to full open position. 13. Start engine (Refer to TM 9-2320-280-10). 14. Remove power steering reservoir cap and turn steering wheel all the way left, hold in place for 5 seconds, then repeat process with steering wheel all the way right. This releases air from the system. 15. Return steering wheel to center position and shut engine off (para. 3-44). 16. Check and add power steering fluid to reach FULL COLD level in reservoir (Refer to TM 9-2320-280-10). 17. Start engine (Refer to TM 9-2320-280-10) and allow engine to idle and reach operating temperature of 190° F to 230° F. 18. Check for proper engine idle speeds and adjust if necessary (para. 3-44). 6.2L engine 650±25 RPM 6.5L engine 700±25 RPM 6.5L detuned engine 700±25 RPM 19. Ensure analyzer valve is in full open position and engine is at proper idle speed. 20. Initial pressure should be 150-250 psi and a flow of 2.50-3.50 gpm. If these specifications aren't present, check installation of analyzer and check power steering system (Refer to TM 9-2320-280-10). 21. With power steering system working properly, partially close analyzer valve until pressure reaches 700 psi. If flow rate varies more than 1 gpm from the initial reading, replace power steering pump (para. 8-24). CAUTION Do not leave analyzer valve fully closed for more than 5 seconds. Severe damage may occur to power steering pump. 22. With engine at idle, close and open analyzer valve three times, recording pressure each time. All readings should be 1300 psi or higher, if pressure is lower, replace power steering pump (para. 8-24). 23. With analyzer valve in the open position, increase engine rpm to 1500 and record fluid flow. If fluid flow varies more than 1 gpm from initial reading, replace power steering pump (para. 8-24). 24. With engine at idle, turn steering wheel all the way left, hold in place for 5 seconds, then repeat process with steering wheel all the way right and record flow rates. If flow rate does not drop to 1 gpm or less, replace steering gearbox (para. 8-21). 25. With engine at idle, turn wheels slightly left and right and release quickly. If pressure does not increase and snap back within 2 seconds, check steering shaft and column for binding and repeat step 15. If pressure still does not increase and snap back, replace steering gearbox (para. 8-21). 26. With engine at idle, push brake pedal down and hold. Record pressure. If pressure varies more than 50 psi from step 22, replace hydro-boost (para. 7-14). 27. With engine at idle, push brake pedal down and release quickly. If pressure does not increase and snap back within 2 seconds, replace hydro-boost (para. 7-14). 28. Shut off engine. Remove power steering analyzer and restore power steering system to original configuration. 29. Bleed power steering system (para. 8-29). NOTE You must be certain that the engine cooling system is working ok, or this test won't tell you anything. If the engine is cold, and everything is working ok, the fan should be disengaged. You can tell by gently revving the engine in neutral with the hood open. If the fan is engaged you will feel a breeze outside the driver's door. If it's disengaged, you won't feel it. If you aren't sure if it's working ok, run the tests in Paragraph 2-25. Change 2 2-469 BYPASS HOSE CONTROL VALVE RETURN HOSE HOSE CLAMP BOLT/PLUG TUBE POWER STEERING PUMP HOSE CLAMP