Brandt GRAIN VAC 5000, Operator And Parts Manual

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50
5.15.3 Replacing the Fan and Bearing Box
1. Remove the front big belt shield.
2. Loosen off the fan drive belt by loosening the nut on the belt idler adjustment bolt and remove the fan
drive belt off of the small pulley.
3. Remove the twenty four 3/8” nuts that hold the fan housing front plate to the fan housing, an 9/16” air
impact wrench works well here.
4. Remove the fan housing front plate assembly from the fan housing. The silicone that is used to seal the
housing will be difficult to pry loose.
5. Remove the small pulley from the fan shaft by pushing the pulley off the bushing with the bolts used to
hold the pulley onto the bushing.
6. Remove the Fan Rotor from the shaft using the bolts used to hold the tapered bushing in the fan hub.
Loosen the setscrew in the tapered bushing and remove the bushing from the shaft.
7. Remove the six mounting bolts which hold the bearing box to the fan front plate. Remove the three
adjustment bolts by loosening the locking nut and unthreading from the fan front plate. Using a sharp
scraper, remove the foam seal from the fan front plate and remove the bearing box.
8. Remove the foam seal and the seal backup washer from the bearing box. The seal backup washer will
be reused on the new installation.
9. Before beginning reassembly, check the tapered bushing in the new fan rotor. The keyway in the
tapered bushing must line up with the small letter ‘K’ that has been stamped in the cast hub bolted to
the rotor. See Fig. 39. If the keyway is not inline with the ‘K’, the rotor will out of balance and cause
premature failure of the bearing box.
10. Slide the seal backup
washer onto the new
bearing box. Apply a
thin layer of clear
silicone to the outside
of the bearing box
where the foam seal
will sit and slide on the
new foam seal.
11. Apply a thin layer of
silicone to the outside
of the fan front plate
where the foam seal
will make contact.
Letter ‘K’ stamped in Hub
Keyway
F
IG
. 39 P
OSITIONING THE
F
AN
T
APERED
H
UB
Tapered Bushing