
45
Fan and Shaft Removal (Fig. 53) —
The fan wheel
and shaft may be removed through inlet side of fan housing.
1. Remove drive belts as described in Fan Shaft Bearing Re-
moval on page 43.
2. Block up fan wheel within housing to prevent dropping
when bearing bolts are removed.
3. Loosen and remove bearing holddown bolts.
4. Remove bearing support channels and inlet ring from one
side.
5. Remove fan shaft and fan wheel from unit.
6. Remove fan shaft from fan wheel.
7. Replace shaft and wheel into fan in the reverse order of
their removal.
8. Inspect bearings and if serviceable, replace on shaft.
9. Align fan wheel and shaft assembly in fan scroll. Check
cutoff location if wheel failure damaged cutoff plate. See
Fig. 54.
10. Tighten bearing holddown bolts, bearing setscrews and
shaft setscrews.
11. Field balancing of shaft and wheel is recommended.
Lubrication
MOTORS — Lubricate in accordance with nameplate at-
tached to motor or with manufacturer’s recommendations
included with motor.
BEARINGS
Fan Bearings — Lubricate fan bearings every 3 months
with suitable bearing grease. Typical lubricants are given in
Table 15.
Inlet Vane and Outlet Damper Bearings — These bearings
are oil-impregnated. Annually lubricate with a few drops of
nondetergent SAE (Society of Automotive Engineers) 20 oil.
Table 15 — Lubricant Data
*Preferred lubricant because it contains rust and oxidation
inhibitors.
IMPORTANT: Replacement shafts must have a diam-
eter tolerance at bearing mount of
nominal.
Carrier-specified parts are recommended.
MANUFACTURER
LUBRICANT
Sunoco
Prestige 42
Texaco
Multipak 2
Texaco
Regal AFB-2*
Mobil
Mobilplex EP No. 1
+ .0000
– .001
Fig. 53 — Fan Shaft and Bearing Removal
Fig. 54 — Fan Cutoff Plate Data (in.)
39L UNIT SIZE
CUTOFF
A
CUTOFF CLEARANCE
B
03
6
5
/
8
7
/
8
06
8
1
08
10
3
/
8
1
1
/
2
10
9
3
/
4
1
3
/
8
12
9
3
/
4
1
3
/
8
15
12
1
5
/
8
18
15
3
/
4
2
21
15
3
/
4
2
25
20
1
/
2
2
11
/
16
Summary of Contents for 39LH
Page 47: ...47 METRIC CONVERSION CHART...