TM 55-1510-219-MTF
b.
Worn fuel control unit/fuel pump coupling.
c.
Engine driven high-pressure fuel pump shaft seal leaking.
d.
Fuel control unit drive spline damage.
e.
Sticking beta mechanism.
E23.
Fluctuating TGT, gas generator speed, and fuel flow.
a.
Faulty instrumentation system.
b.
Fuel pump preformed packing or shaft seal leakage.
c.
Fuel control unit or fuel pump failure.
d.
Worn fuel control unit/fuel pump coupling.
e.
Worn fuel control unit drive spline.
f.
Sticking beta mechanism.
E24.
Fuel leakage at fuel control unit vent.
a.
Leakage at fuel pump shaft seal.
b.
Leakage at preformed packing.
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