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Engine not reversing or starting in only one direction. Reasons

  • Start air valve for that unit may be sticking . The remedy is to give a kick in the opposite direction . Now a different unit will recieve start air due to the change in the crank position
  • The reverse control valve is jammed.
  • The reversing servo motor of the fuel or start air distributer is jammed or gets stuck befor reaching a new end position due to insufficient oil pressure . Therefore the enfine turns on air but no fuel is released as the rotation direction safegaurd block it
  • If the engine is running in one direction and reversed , propellor continues to turn in that direction. Therfore more air and fuel is required for starting against the propelllor force . If the engine still doesnt start , the propellor may tend to turn the engine in the orginal direction ie opposite to the given movement . Therefore the rotational direction safegaurd blocks the fuel
  • Reversing interlock malfunctioning
  • The coil of the solinoid valve for thr desired direction or rotation doesnot get voltage
  • Control air signal for desired direction of rotation doesnot reach the engine . Loosen piping and check the air route or the defective valve.
  • Proximity sensor faulty ( of air distributer or fuek pump servo motor)

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