TM 9-2815 -202-34
When measuring clearances between rotor lobes, 1/2-inch wide feeler gages are
recommended. When measuring clearances of more than 0.005 inch, laminated
feeler gages made up of 0.002, 0.003 or 0.005-inch feeler stock are recommended.
Rotor to rotor measurement should be taken one inch from each end and at center of
Measure clearance between trailing edge of right hand helix rotor and left hand helix rotor,
(CC) clearance, from both inlet and outlet sides. Clearance must be 0.004 to 0.008 inch.
(40) Measure clearance between leading edge of right hand helix rotor and trailing edge of left
hand helix rotor, (C) clearance. Minimum clearance is 0.010 inch.