FAN Propellor Removal and Installation

SERVICE

The fan propellor is secured to the motor shaft by the use of a taper- lock bushing, motor shaft key and three cap screws.

CAUTION: Although the taper-lock method of retaining the propellor onto the motor shaft is simple, it is essential that the following points be read carefully and fully understood. Improper installation can cause a loose flying propellor, and result in serious injury or death.

THREADED BUSHING

HOLES

The threaded holes within the bush- ing are provided for disassembly purposes only. Do not attempt to use these holes for reassembly. They will not allow the parts to lock onto the shaft thereby causing a hazard- ous operating condition.

CLEARANCE HOLES

When reassembling parts, the cap screws must be installed through the untapped clearance holes as shown. This will cause the propellor to be pulled forward onto the tapered bushing, thus locking the parts se- curely onto the motor shaft.

When fan servicing requires re- moval and installation of the propellor, make sure the propellor is removed and reinstalled properly.

1.Lock out the fan power supply, and remove the fan guard and the venturi, as required on some models.

Key

2.Remove the three cap screws from the clearance holes in the taper-lock bushing.

3.Install two grade 5 cap screws into the threaded holes in bush- ing, and turn them by hand until they bottom against the front surface of the propellor.

4.Block propellor to prevent it from turning, and gradually turn the cap screws (up to 1/4 turn at a time) until the propellor breaks loose from the bushing and motor shaft. Carefully

Capscrews installed through threaded holes of bushing

Fan Hub

Split Taper Bushing

Fan blade

installation

removebushingandpropellor.With the propellor free from the bushing, a wheel can be used to pull the bushing off of the motor shaft. Re- attachbushingontopropellortopre- vent the loss of parts.

Note: During manufacture the propellor and bushing are balanced together and are marked with two small dots to identify their original alignment position. Check the bush- ing and propellor to make sure they have alignment marks. Mark the alignment of the propellor and bush- ing, if necessary.

Capscrews installed through threaded holes of bushing

Fan Hub

Split Taper Bushing

Fan blade

removal