TM  10-3930-643-34 HYDRAULIC  SYSTEM  TROUBLESHOOTING  AND  MAINTENANCE.  (cont) 12-3. Loader Control Valve. (Sheet 10 of 14) TESTING/ADJUSTING  -  FORK  CIRCUIT  RELIEF  VALVES 52. 53. 54. 55. 56. 57. 58. 59. Vent  hydraulic  system  pressure,  refer to  TM  10-3930-643-10. Using a 1"   open  end  wrench disconnect  tube  assembly  (14)  from elbow  (27)  on  loader  control  valve (36) and fork valve assembly (45). Disconnect tube assembly (15) from connector  (29). Connect two tees to connector (29) and elbow (27). Tees will have to fit on connector (29) and elbow (27), as well as tube assemblies (14 and 15) and hydraulic pressure gage. Using a 1"   open end wrench and a 10” adjustable wrench, connect tube assemblies (15 and 14) to two tees. Using a 10” adjustable wrench, connect  two  hydraulic  pressure  gages to two tees. Start engine in operator’s compart- ment. Operate tilt and fork controls through four loading cycles, refer to TM  10-3930-643-10. This will bring hydraulic fluid to normal operating temperature. Go to sheet 11 12-22