TM 5-5420-209-12
4-46. Dual Over Center Valve.
This task covers:
a. Test
b. Adjust
c. Replace
INITIAL SETUP
Tools
Equipment Condition:
General Mechanic’s Automotive Tool Kit
Bay removed (para. 2-16).
(Item 1, Appendix B)
Hydraulic Test Equipment
Materials/Parts
Antiseize Tape (Item 19, Appendix E)
NOTE
There are two dual over center valves on transporter. The maintenance procedures are the same for both.
a. Test. (figures 4-51 and 4-52)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
NOTE
Dual over center valve removed for test. See para. c. below.
Connect a 0-6,000 psi (0-41,307 kpa) hydraulic pressure source and gage to a cylinder port 2.
Connect a 0-300 psi (0-2,068 kpa) hydraulic pressure source and gage to cylinder port 1.
Connect valve port 2 to hydraulic reservoir and 0-30 GPM flow meter.
Plug valve port 1.
Set pressure at cylinder port 2 to 0 psi (0 kpa).
Increase cylinder port 1 pressure in 50 psi (345 kpa) and record the pressure at which flow occurs between
cylinder port 2 to valve port 2.
Increase cylinder port 1 pressure up to 250 psi (1,705 kpa) or until flow occurs between cylinder port 2 and
valve port 2 at 0 psi (0 kpa).
Adjust valve (see para. b. below) if valve does not perform within tolerances.
Reduce all pressures to 0 psi (0 kpa) and disconnect connections.
4-168
