YORK INTERNATIONAL
48
Maintenance
FORM 100.50-NOM1 (604)
11. Torque all hardware.
Disconnect and lock-out power from
the unit anytime service is being per-
formed on the fan sec tion. Failure to
do so could result in serious in ju ry or
death due to the fan turning on while
work is in progress.
Fan Motor
1. Shut off unit power and lock out.
2. Disconnect and tag power wires at motor
terminals.
3. Loosen motor brace-to-mount ing-rail at tach ing
bolts.
4. Mark belt as to position. Re move and set aside
belts.
5. Remove motor bracket hold down bolts.
6. Remove motor pulley and set aside.
7. Remove motor.
8. Install new motor. Re as sem ble by re vers ing steps 1 -
6. Be sure to re in stall mul ti ple belts in their orig i nal
po si tion. Use a complete new set if re quired. Do not
stretch belts over sheaves. Re view the sec tions on
motor and sheave in stal la tion, sheave align ment,
and belt tensioning discussed pre vi ous ly.
9. Reconnect motor leads and restore power. Check fan
for proper ro ta tion as described in Start-Up Check
List.
Fan Shaft Bearings
General –
When removing and replacing the bearings,
care should be taken to en sure that the area where the
bear ings
Þ
t on the shaft does not be come scored or
dam aged. The shaft in this area should be thoroughly
cleaned before the bearing is removed and again be fore
the new bear ing is installed.
Mounting Details –
1. Check the shaft - it should be straight, free of burrs
and full size. Be sure the bearing is not seated on a
worn section of shafting.
2. Make certain any set screws are not ob struct ing the
bearing bore.
3. Align the bearing in its hous ing and slide the bear ing
into position on shaft - never hammer the ends of
the inner race. If nec es sary, use a brass bar or pipe
against the inner race to drift bearing into place -
never hit the housing, as bearing dam age may re sult.
Make sure there is lu bri cant between the bear ing
outer ring and the hous ing.
4. Fasten the bearing housing to the unit mount ing sup-
port with hex head cap screws, wash ers, new lock
wash ers and hex nuts before se cur ing the bearing
to the shaft. This permits the bearing to align itself
in po si tion along the shaft and eliminates any pos-
si bil i ty of cramp ing loads.
5. Rotate the shaft to make cer tain it turns free ly.
6. Bearings may employ one of several different
meth ods to lock the bear ing to the shaft.
Shaft should be free from burrs. If old
shaft is used, be sure a ball bearing is
not seat ed on worn section and shaft
is not bent.
There are various degrees of self-alignment in bear-
ings of the same man u fac tur er. The force required
for the self-alignment of the bear ings used in YORK
man u fac tured units has been spec i
Þ
ed and is close ly
monitored at the fac to ry. If it is nec es sary to purchase
a bearing locally, be sure it can be worked around in the
housing with a short shaft made of wood or other soft
material placed in the bearing.
