REPLACEMENT BLOWER FOR ALPHA
86, 78, 76A SERIES, AND 374A AMPLIFIERS

The original blower motor, manufactured by Howard Industries,
is no longer available. An exact replacement motor assembly is
available from Alpha/Power. This includes the motor, squirrel-cage
fan, and motor bracket with foam base cemented in place.

1) The motor bracket is glued to the chassis, and the black blower
housing is held in place by the tube deck, a screw, and double-faced
tape. Remove the tubes, tube deck screws and blower housing screw
and lift up the tube deck. Pry the motor bracket off the chassis and lift
out the motor and housing together. Remove the squirrelcage blower
from motor shaft to separate the motor and housing.

2) Scrape off the old foam, glue, and tape from the chassis.
Mount the new squirrelcage blower on the new motor after putting
the motor shaft through the black blower housing. Glue the motor
bracket (with the new foam on the bottom) to the chassis as you set
the assembly into the amp. Use 3m Scotch Adhesive #4475. Be sure
the back of the motor is not touching the chassis. Put the blower
housing screw in place to check the alignment of the housing and
motor bracket before the glue sets up.

3) Allow the glue to dry for 24 hours. Remove the blower housing
screw and gently rotate the housing clockwise to gain access to the
backing of the double-faced tape under the left end of the housing.
Remove the plastic backing and carefully lower the housing to the
chassis, aligning the hole in the chassis and the fan housing while
setting the housing on the chassis. The tape will secure the two together.
Tip the housing up and counter-clockwise and remove the backing
from the tape on the right side of the housing. Set the housing in place
and tighten the screw, lockwasher and nut holding it to the chassis.

4) Set tube deck in place and replace all tube deck screws.
Install tubes, skirts and chimneys.

The blower motor is designed for 115VAC, 60HZ and will
run about 20% slower when used on 50Hz. It is in use in amps
in Europe and cooling is adequate.

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