surface of the housing is slightly scored
oil seals are chrome flashed and the car-
or burred, it may be cleaned up with em-
r i e r s a r e l i q u i d n i t r i d e d . When replace-
ery cloth.
ment of an oil seal ring or carrier is
necessary, both parts must be replaced
Check t h e f i n i s h e d e n d s o f t h e b l o w e r
together.
housing for flatness and burrs. The end
plates m u s t s e t f l a t a g a i n s t t h e b l o w e r
Inspect the blower rotor lobes, especially
housing.
the sealing ribs, for burrs and scoring.
Rotors must be smooth for efficient oper-
The finished inside face of each end
If the rotors are
ation of the blower.
If the
plate m u s t b e s m o o t h a n d f l a t .
slightly scored or burred, they may be
slightly
scored or
finished
face
is
cleaned up with emery cloth.
burred, it may be cleaned up with emery
cloth.
Examine the rotor shaft serrations for
wear, burrs, or peening. Also, inspect
Examine the serrations in the lower blow-
t h e bearings and oil seal contact surfaces
er timing gears for wear and peening.
for wear and scoring.
Also check the teeth for wear, chipping
or damage.
If the gears are worn to the
inspect the inside surface of the blower
point where the backlash between the
housing for burrs and scoring. The in-
gear teeth exceeds 0.004", or damaged
side surface must be smooth for efficient
If the inside
operation o f t h e b l o w e r .
F i g u r e 11D-11. B l o w e r D e t a i l s