TM 55-1520-240-T
7-1.25 ROTOR SYSTEM STARTS TO TURN WHEN POWER XFR NO. 1 AND NO. 2 SWITCHES ARE SET TO ON
7-1.25
FAULT ISOLATION PROCEDURE
INITIAL SETUP
Equipment Condition:
Applicable Configurations
TM 55-1520-240-23:
Battery Connected
All
Electrical Power On
Tools:
Hydraulic Power On
Aircraft Mechanic’s Tool Kit,
NSN 5180-00-323-4692
Crissair Check Valve Tool Kit
Materials:
None
Personnel Required:
Aircraft Pneudraulics Repairer
Medium Helicopter Repairer
References:
TM 55-1520-240-23
General Safety Instructions:
Make sure area around aircraft is clear of
personnel before performing this task. Ro-
tor blades can cause serious injury to
personnel.
TM 43-0104
SET POWER XFR NO. 1
SET POWER XR NO. 2
SWITCH TO ON. DOES ROTOR
SWITCH TO ON. DOES ROTOR
SYSTEM TURN BACKWARDS?
REPEAT OPERATIONAL CHECK.
SYSTEM TURN BACKWARDS?
REPLACE THE CHECK VALVE
ON NO. 2 POWER CONTROL
MODULE THAT PREVENTS
BACK FLOW TO NO. 2 FLIGHT
CONTROL HYDRAULIC PUMP.
REFER TO TM 43-0104. IF
CHROME RIVET AND WASHER
ARE NO LONGER INSTALLED IN
CENTER OF OLD CHECK VALVE,
RECOVER THE RIVET AND
WASHER FROM THE HYDRAU-
LIC TUBES TO THE PUMP.
CHECK TUBE 145H1803-11
FIRST.
7-70
Change 8
END OF TASK
