Caterpillar Cat 621G Wheel Tractor (Prefix DBB) Service Repair Manual (DBB00001 and up).pdf

Service Repair Manual
Models
621G Wheel Tractor

Shutdown SIS
Previous Screen
Product: WHEEL TRACTOR
Model: 621G WHEEL TRACTOR DBB
Configuration: 621G Wheel Tractor DBB00001-UP (MACHINE) POWERED BY C15 Engine
Disassembly and Assembly
621G and 623G
Wheel Tractor-Scrapers
Power Train
Media Number -RENR7497-00 Publication Date -01/08/2005 Date Updated -04/08/2005
i02121676
Torque Converter - Assemble
SMCS - 3101-016
Assembly Procedure
Table 1
Required Tools
Tool Part Number Part Description Qty
A 2P-8312 Retaining Ring Pliers 1
B 1P-0510 Driver Group 1
D 8T-5096 Dial Indicator Group 1
Illustration 1 g00528674
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1. Use Tooling (B) and a suitable press in order to install sleeve bearing (33) to flange (32) .
2. Install bolts (31) and flange (32) to housing (9). Tighten bolts (31) to the torque 120 ± 15
N·m (89 ± 11 lb ft).
3. Install thrust bearing (29) and thrust race (30) to housing (9) .
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4. Install torque converter turbine (23) and clamp ring (28) to hub (3) .
5. Install bolts (27) to torque converter turbine (23). Tighten bolts (27) to a torque of 50 ± 7
N·m (37 ± 5 lb ft). Install thrust race (26) to hub (3) .
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6. Install thrust race (25) and thrust bearing (24) to hub (3) .
7. Install torque converter turbine (23) and hub (3) as a unit to housing (9) .
8. Use Tooling (B) and a suitable press in order to install sleeve bearing (22) to carrier
assembly (12). Install thrust bearing (21) to carrier assembly (12) .
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9. Install side plate (20) to torque converter stator (13). Use Tooling (A) in order to install
retaining ring (19) to torque converter stator (13) .
10. Use Tooling (B) and a suitable press in order to install freewheel cam (18) to torque
converter stator (13) .
Personal injury can result from being struck by parts propelled by a
released spring force.
Make sure to wear all necessary protective equipment.
Follow the recommended procedure and use all recommended tooling to
release the spring force.
11. Install torque converter stator (13) to carrier assembly (12). Install freewheel springs (17)
and freewheel rollers (16) to freewheel cam (18). Always install new freewheel springs (17)
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and freewheel rollers (16). Install freewheel springs (17) with the maximum number of
loops in freewheel springs (17) to the outside of freewheel cam (18). Torque converter
stator (13) should turn freely in the counterclockwise direction. Torque converter stator (13)
should not turn freely in the clockwise direction.
12. Install thrust race (15) to torque converter stator (13). Use Tooling (A) in order to install
retaining ring (14) to torque converter stator (13) .
13. Install carrier assembly (12) and torque converter stator (13) as a unit to housing (9) .
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14. Install thrust bearing (11) to carrier assembly (12) .
15. Install impeller hub (8) to torque converter impeller (5). Install metal seal ring (10) to torque
converter impeller (5) .
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16. Install clamp plate (7), the washers, and bolts (6) to impeller hub (8). Tighten bolts (6) to a
torque of 50 ± 7 N·m (37 ± 5 lb ft).
17. Install bolts (4) and the washers to torque converter impeller (5). Tighten bolts (4) to a
torque of 50 ± 7 N·m (37 ± 5 lb ft).
18. Use Tooling (B) and a suitable press in order to install the sleeve bearing in carriage support
assembly (2). Install the sleeve bearing until the sleeve bearing is flush with the outside
machined surface of carriage support assembly (2) .
19. Install carriage support assembly (2) to hub (3). Use Tooling (A) in order to install retaining
ring (1) to carriage support assembly (2) .
20. Install Tooling (D) to the torque converter, as shown. The edge of Tooling (D) must be in
contact with the edge of carrier assembly (12), as shown. Move hub (3) up and down with a
screwdriver. The end play of hub (3) must be 0.13 to 1.96 mm (0.005 to 0.077 inch).
End By: Install the torque converter. Refer to Disassembly and Assembly, "Torque Converter -
Install".
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Shutdown SIS
Previous Screen
621G and 623G
Power Train
i02036666
Torque Converter - Install
SMCS - 3101-012
Installation Procedure
Table 1
Required Tools
A 1P-2420 Transmission Repair Stand 1
B 138-7575 Link Bracket 2
C 2P-8312 Retaining Ring Pliers 1
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1. Attach Tooling (B) and a suitable lifting device to torque converter (3). Position torque
converter (3) onto transmission planetary (1). The weight of torque converter (3) is
approximately 70 kg (154 lb). Install nuts (7) that hold torque converter (3) to transmission
planetary (1) .
2. Install washer (5) to shaft (6). Use Tooling (C) in order to install retaining ring (4) to shaft
(6) .
3. Remove transmission planetary (1) and torque converter (3) as a unit from Tooling (A). The
weight of transmission planetary (1) and torque converter (3) as a unit is approximately 703
kg (1550 lb).
4. Put transmission planetary (1) and torque converter (3) as a unit onto blocks. Remove
Tooling (B) and the suitable lifting device from torque converter (3) .
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5. Attach Tooling (B) and a suitable lifting device to case (2). Install case (2) onto Tooling (A)
(not shown). The weight of case (2) is approximately 90 kg (200 lb).
6. Attach Tooling (B) and a suitable lifting device to transmission planetary (1) and torque
converter (3) as a unit. Install transmission planetary (1) and torque converter (3) as a unit to
case (2). The weight of transmission planetary (1) and torque converter (3) as a unit is
approximately 703 kg (1550 lb).
7. Install the bolts that hold transmission planetary (1) to case (2) .
End By:
a. Install the transfer gears. Refer to Disassembly and Assembly, "Transfer Gears - Connect".
b. Install the transmission hydraulic control valve. Refer to Disassembly and Assembly,
"Transmission Hydraulic Control Valve - Install".
Copyright 1993 - 2021 Caterpillar Inc.
All Rights Reserved.
Private Network For SIS Licensees.
Sun Mar 7 21:04:55 UTC+0800 2021
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Shutdown SIS
Previous Screen
621G and 623G
Power Train
i02301155
Transfer Gears - Disassemble
SMCS - 3159-015
Disassembly Procedure
Table 1
Required Tools
A 138-7575 Link Bracket 1
B
8B-7548 Push-Puller Tool Gp 1
8B-7551 Bearing Puller Gp 1
1P-0498 Drive Plate 1
C
5P-4170 Step Plate 1
1P-2321 Combination Puller 1
D
8B-7554 Bearing Cup Puller Gp 1
5P-4170 Step Plate 1
1P-0518 Drive Plate 1
E
8B-7560 Step Plate 1
5F-7345 Screw 1
8B-7554 Bearing Cup Puller Gp 1
F -
Bolts
3/8" - 16 NC by 3 inch
3
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Start By:
a. Remove the transfer gear case. Refer to Disassembly and Assembly, "Transfer Gears -
Remove".
b. Remove the transmission oil filter base. Refer to Disassembly and Assembly, "Transmission
Oil Filter Base - Remove and Install".
c. Remove the transmission scavenge pump. Refer to Disassembly and Assembly,
"Transmission Scavenge Pump - Remove".
d. Remove the transmission oil pump. Refer to Disassembly and Assembly, "Transmission Oil
Pump - Remove".
NOTICE
Care must be taken to ensure that fluids are contained during
performance of inspection, maintenance, testing, adjusting, and repair
of the product. Be prepared to collect the fluid with suitable containers
before opening any compartment or disassembling any component
containing fluids.
Refer to Special Publication, NENG2500, "Dealer Service Tool
Catalog" for tools and supplies suitable to collect and contain fluids on
Cat®
products.
Dispose of all fluids according to local regulations and mandates.
NOTICE
Keep all parts clean from contaminants.
Contamination of the hydraulic system with foreign material will
reduce the service life of the hydraulic system components.
To prevent contaminants from entering the hydraulic system, always
plug or cap the lines, fittings, or hoses as they are disconnected. Cover
any disassembled components and clean them properly before
assembly.
Clean the hydraulic system properly after any major component
exchange or especially after a component failure, to remove any
contamination.
1. Put identification marks on components for installation purposes.
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2. Remove the bolts that secure bearing cage (1) to the transfer gear case. Use Tooling (F) in
order to separate bearing cage (1) from the transfer gear case.
3. Remove bearing cage (1), shims (2), and pump drive gear (3) from the transfer gear case.
5. Remove bearing cage (4), shims (5), and gear (6) from the transfer gear case.
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6. Remove bearing cups (7) and (8) from the transfer gear case. Attach Tooling (A) and a
suitable lifting device onto the transfer gear case. The weight of the transfer gear case is
approximately 340 kg (750 lb). Turn over the transfer gear case. Remove Tooling (A).
8. Remove bearing cage (9), shims (10), and gear (11) from the transfer gear case.
9. Remove bearing cup (12) from the transfer gear case. Attach Tooling (A) and a suitable
lifting device onto the transfer gear case. Turn over the transfer gear case.
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10. Remove bolts (13) that secure bearing cage (14) to the transfer gear case. If necessary, rotate
the gear until the three threaded holes are visible in bearing cage (14). Install Tooling (F)
through gear (15) and into bearing cage (14). Tighten Tooling (F) evenly until bearing cage
(14) and gear (15) separate from the transfer gear case. Remove bearing cage (14) and gear
(15) as a unit from the transfer gear case.
11. Remove retaining ring (16) from gear (15). Remove bearing (17) and bearing cage (14)
from gear (15).
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12. Remove bearing (17) from bearing cage (14).
13. Remove bolts (19) and separate gear (20) from gear (11). Use Tooling (B) to remove
bearing cone (18) from gear (11). Repeat the procedure for the bearing cone on the opposite
side of the gear.
14. Use Tooling (C) to remove bearing cone (21) from gear (6). Repeat the procedure for the
bearing cone on the opposite side of gear (6).
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15. Use Tooling (C) to remove bearing cone (22) from gear (3). Repeat the procedure for the
bearing cone on the opposite side of gear (3).
16. Use Tooling (D) to remove bearing cup (23) from bearing cage (4). Remove O-ring seal
(24) from bearing cage (4).
17. Remove bearing cup (25) from bearing cage (9).
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18. Use Tooling (E) to remove bearing cup (26) from bearing cage (1). Remove O-ring seal (27)
from bearing cage (1).
Copyright 1993 - 2021 Caterpillar Inc.
All Rights Reserved.
Private Network For SIS Licensees.
Sun Mar 7 21:05:51 UTC+0800 2021
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Shutdown SIS
Previous Screen
621G and 623G
Power Train
i07232119
Transfer Gears - Assemble
SMCS - 3159-016
Assembly Procedure
Table 1
Required Tools
A 138-7575 Link Bracket 1
G 1P-0510 Driver Group 1
H 8T-5096 Dial Indicator 1
NOTICE
Keep all parts clean from contaminants.
Contamination of the hydraulic system with foreign material will
reduce the service life of the hydraulic system components.
To prevent contaminants from entering the hydraulic system, always
plug or cap the lines, fittings, or hoses as they are disconnected. Cover
any disassembled components and clean them properly before
assembly.
Clean the hydraulic system properly after any major component
exchange or especially after a component failure, to remove any
contamination.
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1. Clean all parts and inspect all parts. If any parts are worn or damaged, use new parts for
replacement.
2. Lubricate O-ring seals with the lubricant that is being sealed.
3. Install bearing (17) into bearing cage (14).
4. Use Tooling (G) to install bearing (17) and bearing cage (14) to gear (15). Install bearing
(17) and bearing cage (14) until the retaining ring groove is visible. Install retaining ring
(16) to gear (15).
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5. Position gear (15) and bearing cage (14) in the transfer gear case. Install bolts (13) that
secure bearing cage (14) to the transfer gear case. Tighten bolts (13) to a torque of
55 ± 10 N·m (41 ± 7 lb ft).
6. Install O-ring seal (27) onto bearing cage (1). Lower the temperature of bearing cup (26).
Install bearing cup (26) to bearing cage (1). Check that bearing cup (26) is seated in the bore
of bearing cage (1).
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7. Lower the temperature of bearing cup (25). Install bearing cup (25) to bearing cage (9).
Check that bearing cup (25) is seated in the bore of bearing cage (9).
8. Install O-ring seal (24) to bearing cage (4). Lower the temperature of bearing cup (23).
Install bearing cup (23) to bearing cage (4). Check that bearing cup (23) is seated in the bore
of bearing cage (4).
9. Raise the temperature of bearing cone (22). Install bearing cone (22) on gear (3). Repeat the
procedure for the bearing cone on the opposite side of gear (3).
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10. Raise the temperature of bearing cone (21). Install bearing cone (21) on gear (6). Repeat the
procedure for the bearing cone on the opposite side of gear (6).
11. Raise the temperature of bearing cone (18). Install bearing cone (18) on gear (11). Repeat
the procedure for the bearing cone on the opposite side of gear (11).
12. Position gear (20) on gear (11). Install bolts (19). Tighten bolts (19) to a torque of
55 ± 10 N·m (41 ± 7 lb ft). Attach Tooling (A) and a suitable lifting device onto the transfer
gear case. The weight of the transfer gear case is approximately 340 kg (750 lb). Turn over
the transfer gear case. Remove Tooling (A).
13. Lower the temperature of bearing cup (12). Use Tooling (G) to install bearing cup (12) to
the transfer gear case. Check that bearing cup (12) is seated in the bore of the transfer gear
case.
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14. Position gear (11) in the transfer gear case. Install bearing cage (9) and shims (10). Install
bolts (28) that hold bearing cage (9) in position. Tighten bolts (28) to a torque of
55 ± 10 N·m (41 ± 7 lb ft).
15. Position Tooling (H) in the transfer gear case, as shown. Make sure that the dial indicator is
in contact with gear (11). Use a pry bar to move gear (11) up and down. Adjust shims (10)
to obtain an end play of 0.15 ± 0.05 mm (0.006 ± 0.002 inch). Tighten bolts (28) to a torque
of 55 ± 10 N·m (41 ± 7 lb ft).
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16. Use Tooling (G) to install bearing cups (7) and (8) to the transfer gear case. Check that
bearing cups (7) and (8) is seated in the bore of the transfer gear case.
17. Position gear (6) in the transfer gear case with the internal snap ring groove facing up.
Install bearing cage (4) and shims (5). Install the bolts (29) that hold bearing cage (4) in
position. Tighten bolts (29) to a torque of 55 ± 10 N·m (41 ± 7 lb ft).
18. Attach Tooling (A) and a suitable lifting device to the transfer gear case. Place the transfer
gear case on wood blocks, as shown. Position Tooling (H) on the transfer gear case, as
shown. Make sure that the dial indicator is in contact with gear (6). Use a pry bar to move
gear (6) up and down. Adjust shims (5) to obtain an end play of 0.15 ± 0.05 mm
(0.006 ± 0.002 inch). Tighten bolts (29) to a torque of 55 ± 10 N·m (41 ± 7 lb ft).
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19. Position gear (3) in the transfer gear case. Install bearing cage (1) and shims (2). Install the
bolts (30) that hold bearing cage (1) in position. Tighten bolts (30) to a torque of
55 ± 10 N·m (41 ± 7 lb ft).
20. Position Tooling (H) on the transfer gear case, as shown. Make sure that the dial indicator is
in contact with gear (3). Use a pry bar to move gear (3) up and down. Adjust shims (2) to
obtain an end play of 0.15 ± 0.05 mm (0.006 ± 0.002 inch). Tighten bolts (30) to a torque of
55 ± 10 N·m (41 ± 7 lb ft).
End By:
a. Install the transmission oil pump. Refer to Disassembly and Assembly, "Transmission Oil
Pump - Install".
b. Install the transmission scavenge pump. Refer to Disassembly and Assembly, "Transmission
Scavenge Pump - Install".
c. Install the transmission oil filter base. Refer to Disassembly and Assembly, "Transmission
Oil Filter Base - Remove and Install".
d. Install the transfer gear case. Refer to Disassembly and Assembly, "Transfer Gears -
Install".
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Shutdown SIS
Previous Screen
621G and 623G
Power Train
i02127894
Transmission Planetary - Disassemble
SMCS - 3030-015
Disassembly Procedure
Start By:
A. Separate the transfer gears from the transmission. Refer to Disassembly and Assembly,
"Transmission and Transfer Gears - Separate".
B. Remove the transmission hydraulic control valve. Refer to Disassembly and Assembly,
"Transmission Hydraulic Control Valve - Remove".
Table 1
Required Tools
A 1P-7407 Eyebolt 2
B FT-0833 Clamp 2
C 2P-8312 Retaining Ring Pliers 1
D FT-1335 Transmission Fixture 1
E 1P-0520 Driver Gp 1
F 1P-2420 Transmission Repair Stand 2
G 1P-7405 Eyebolt 2
H 3/8 - 16 NC Forcing Screw 4
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NOTICE
Care must be taken to ensure that fluids are contained during
performance of inspection, maintenance, testing, adjusting and repair
of the product. Be prepared to collect the fluid with suitable containers
before opening any compartment or disassembling any component
containing fluids.
Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop
Products Guide" for tools and supplies suitable to collect and contain
fluids on Caterpillar products.
Dispose of all fluids according to local regulations and mandates.
1. Install Tooling (A) and a suitable lifting device onto transmission assembly (1). Position
transmission assembly (1) onto Tooling (F). The weight of the transmission assembly is
approximately 703 kg (1550 lb).
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Caterpillar Cat 621G Wheel Tractor (Prefix DBB) Service Repair Manual (DBB00001 and up).pdf

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Caterpillar Cat 621G Wheel Tractor (Prefix DBB) Service Repair Manual (DBB00001 and up).pdf