Caterpillar cat ec20n forklift lift trucks service repair manual sn：a4ec2 10200 and up by 163048

Service Manual Chassis & Mast EC15N, EC18N A4EC1-10200-up A4EC1-20200-up

EC20N, EC25N A4EC2-10200-up A4EC2-20200-up

EC25EN, EC25LN, EC30N A4EC3-20200-up A4EC3-30200-up A4EC3-40200-up

99759-6K110

TABLE OF CONTENTS Chapter 1: General Information Scope ........................................................................................................................................... 1.1 Truck Models Covered ................................................................................................................. 1.1 Nameplate and Serial Number Locations .................................................................................... 1.2 Dimensions................................................................................................................................... 1.3 Dimensions Chart .................................................................................................................... 1.4 General Information (Standard Models)....................................................................................... 1.5

Chapter 2: Front Axle & Reduction Differential Front Axle Description ................................................................................................................................... 2.1 General Information ................................................................................................................. 2.1 Removal ....................................................................................................................................... Front Wheels ............................................................................................................................ Method 1.............................................................................................................................. Method 2.............................................................................................................................. Method 3..............................................................................................................................

2.2 2.2 2.3 2.3 2.3

Installation .................................................................................................................................... 2.4 Disassembly ................................................................................................................................. 2.5 Removing Front Wheel Hub ..................................................................................................... 2.6 Inspection after Disassembly ....................................................................................................... 2.7 Reassembly.................................................................................................................................. Axle Housing ............................................................................................................................ Front Wheel Hub ...................................................................................................................... Hub Bearing Preload................................................................................................................ Installation and Setting Preload...........................................................................................

2.8 2.8 2.8 2.10 2.10

Reduction Differential Description ................................................................................................................................... 2.11 Disassembly ................................................................................................................................. 2.12 Inspection after Disassembly ....................................................................................................... 2.13 Reduction Gear ........................................................................................................................ 2.13 Differential ................................................................................................................................ 2.13 Reassembly.................................................................................................................................. 2.14 Inspection and Adjustment........................................................................................................... Side Bearing Preload ............................................................................................................... Reduction Gear Backlash ........................................................................................................ Reduction Gear Face Runout .................................................................................................. Tooth Contact ........................................................................................................................... Tooth Contact Adjustment ........................................................................................................

2.16 2.16 2.16 2.17 2.17 2.18

TABLE OF CONTENTS Chapter 3: Transfer Assembly Description ................................................................................................................................... 3.1 Disassembly ................................................................................................................................. 3.2 Disassembly Sequence................................................................................................................ 3.2 Inspection after Disassembly ....................................................................................................... 3.4 Reassembly.................................................................................................................................. 3.5

Chapter 4: Rear Axle Description ................................................................................................................................... 4.1 Rear Wheels................................................................................................................................. 4.2 Removal ................................................................................................................................... 4.2 Installation ................................................................................................................................ 4.4 Rear Axle ..................................................................................................................................... Removal ................................................................................................................................... Installation ................................................................................................................................ Disassembly ............................................................................................................................. Inspection after Disassembly ................................................................................................... Reassembly..............................................................................................................................

4.7 4.7 4.8 4.9 4.11 4.12

Inspection and Adjustment........................................................................................................... 4.17 Minimum Turning Radius Adjustment....................................................................................... 4.17

Chapter 5: Brake System Description ................................................................................................................................... 5.1 Automatic Adjusting Device ..................................................................................................... 5.1 General Information ................................................................................................................. 5.1 Master Cylinder Disassembly ............................................................................................................................. 5.2 Inspection after Disassembly ................................................................................................... 5.3 Reassembly.............................................................................................................................. 5.3 Service Brakes Disassembly (EC15N–EC18N) ................................................................................................................. (EC20N–EC30N) ................................................................................................................. Inspection after Disassembly ................................................................................................... Reassembly (EC15N–EC18N) ................................................................................................................. (EC20N–EC30N) ................................................................................................................. Wheel Cylinders Disassembly ............................................................................................................................. Inspection after Disassembly ................................................................................................... Reassembly.............................................................................................................................. Inspection and Adjustment....................................................................................................... ii

5.4 5.5 5.7 5.8 5.9 5.12 5.13 5.13 5.14

TABLE OF CONTENTS Chapter 6: Steering System Steering System Description ................................................................................................................................... Steering System ...................................................................................................................... Oil Flow Sequence .............................................................................................................. General Information.............................................................................................................

6.1 6.1 6.1 6.1

Steering Gear Steering Wheel Removal ................................................................................................................................... 6.2 Installation ................................................................................................................................ 6.2 Steering Gear............................................................................................................................... 6.3 Inspection after Removal ............................................................................................................. 6.4 Disassembly ................................................................................................................................. Working Rules and Tips ........................................................................................................... Suggestions ............................................................................................................................. Inspection after Disassembly ...................................................................................................

6.5 6.6 6.6 6.6

Reassembly.................................................................................................................................. 6.7 Steer Pump Removal ....................................................................................................................................... 6.8 Installation .................................................................................................................................... 6.9 Disassembly ................................................................................................................................. Sequence ................................................................................................................................. Working Rules and Tips ........................................................................................................... Suggestions ............................................................................................................................. Inspection after Disassembly ...................................................................................................

6.10 6.10 6.11 6.11 6.13

Reassembly.................................................................................................................................. Sequence ................................................................................................................................. Suggestions ............................................................................................................................. Inspection after Reassembly....................................................................................................

6.14 6.14 6.15 6.17

Chapter 7: Hydraulic System Hydraulic System Description ................................................................................................................................... Schematic ............................................................................................................................... Hydraulic Tank.......................................................................................................................... Hydraulic Pump ....................................................................................................................... Control Valve ............................................................................................................................ Lift and Tilt Cylinders................................................................................................................ Down Safety Valve ...................................................................................................................

7.1 7.1 7.3 7.4 7.6 7.7 7.8

Removal and Installation Warning................................................................................................ 7.9

iii

TABLE OF CONTENTS Hydraulic Pump Removal ....................................................................................................................................... 7.10 Installation .................................................................................................................................... 7.11 Disassembly ................................................................................................................................. 7.12 Working Rules and Tips ........................................................................................................... 7.12 Suggestions ............................................................................................................................. 7.14 Inspection after Disassembly ....................................................................................................... Body ......................................................................................................................................... Mounting Flange Face ............................................................................................................. Bushes and Balance Plate....................................................................................................... Gears .......................................................................................................................................

7.16 7.16 7.16 7.16 7.16

Reassembly.................................................................................................................................. 7.17 Inspection after Reassembly........................................................................................................ 7.21 Control Valve Removal ....................................................................................................................................... 7.22 Installation .................................................................................................................................... 7.23 Disassembly ................................................................................................................................. 7.24 Suggestions ................................................................................................................................. 7.25 Reassembly.................................................................................................................................. 7.25 Lift and Tilt Cylinders Removal Lift Cylinders ............................................................................................................................ 7.26 Tilt Cylinders ............................................................................................................................ 7.29 Disassembly Lift Cylinders ............................................................................................................................ 7.31 Tilt Cylinders ............................................................................................................................ 7.32 Inspection after Disassembly ....................................................................................................... 7.33 Precautions for Reassembly ........................................................................................................ 7.33 Inspection and Adjustment Hydraulic Tank.............................................................................................................................. 7.34 Control Valve ................................................................................................................................ 7.35 Lift and Tilt Cylinders.................................................................................................................... 7.38 Adjusting Method ..................................................................................................................... 7.39 Testing ...................................................................................................................................... 7.40

Chapter 8: Mast and Forks Description ................................................................................................................................... 8.1 Removal and Installation.............................................................................................................. 8.2 iv

TABLE OF CONTENTS Disassembly ................................................................................................................................ 8.4 Inspection after Disassembly ....................................................................................................... 8.6 Reassembly.................................................................................................................................. 8.7 Inspection and Adjustment........................................................................................................... Forks ........................................................................................................................................ Chain Tension Adjustment ....................................................................................................... Clearance Adjustment on Lift Bracket...................................................................................... Mast Clearance Adjustment ..................................................................................................... Main Roller Shim Replacement ............................................................................................... Mast Strip Adjustment.............................................................................................................. Tilt Angle Adjustment ............................................................................................................... Lift Cylinder Stroke Adjustment................................................................................................ Bleeding Lift Cylinders .............................................................................................................

8.8 8.8 8.9 8.10 8.13 8.15 8.15 8.16 8.17 8.17

Service Data ................................................................................................................................ 8.18 Troubleshooting ............................................................................................................................ 8.20

Chapter 9: Troubleshooting Front Axle and Reduction Differential .......................................................................................... 9.1 Brake System ............................................................................................................................... 9.2 Steering System........................................................................................................................... 9.4 Hydraulic System ......................................................................................................................... 9.6 Rear Axle ..................................................................................................................................... 9.8 Mast and Forks ............................................................................................................................ 9.9

Chapter 10: Maintenance Service Data Maintenance Service Data........................................................................................................... Front Axle and Reduction Differential ...................................................................................... Transfer Case ........................................................................................................................... Rear Axle ................................................................................................................................. Brake System ........................................................................................................................... Steering System,...................................................................................................................... Hydraulic System ..................................................................................................................... Mast and Forks (Simplex Mast) ............................................................................................... Mast and Forks ........................................................................................................................

10.1 10.1 10.3 10.4 10.6 10.11 10.13 10.16 10.17

Tightening Torques for Standard Bolts and Nuts ......................................................................... Fine Thread—With Spring Washer .......................................................................................... Fine Thread—Without Spring Washer ..................................................................................... Coarse Thread—With Spring Washer...................................................................................... Coarse Thread—With Spring Washer......................................................................................

10.18 10.18 10.18 10.18 10.18

Tightening Torques for Standard Bolts and Nuts with Standard Threads .................................... 10.19 Coarse Thread—Inches ........................................................................................................... 10.19 v

TABLE OF CONTENTS Tightening Torques for Taperlock Studs ....................................................................................... 10.19 Coarse Threadâ&#x20AC;&#x201D;Inches ........................................................................................................... 10.19 Maintenance Chart....................................................................................................................... 10.20 Planned Replacement Parts ........................................................................................................ 10.26 Lubrication Information................................................................................................................. Chart ........................................................................................................................................ Fuel and Lubricant Specifications ............................................................................................ Recommended Brands of Lubricants.......................................................................................

10.27 10.27 10.28 10.28

Weight of Major Components (Approximate) ............................................................................... 10.29 Special Service Tools ................................................................................................................... 10.30 Special Tool Illustrations........................................................................................................... 10.31 Inspection Guide .......................................................................................................................... 10.34

GENERAL INFORMATION

Scope This service manual deals with all components or systems of the Cat lift trucks, except for the electrical system, which is covered in a separate manual.

8609141A

Truck Models Covered This service manual furnishes service and maintenance information for the following trucks.

Truck Model

Serial Number

EC15N, EC18N

A4EC1-10200-up A4EC1-20200-up A4EC2-10200-up A4EC2-20200-up A4EC3-20200-up A4EC3-30200-up A4EC3-40200-up

EC20N, EC25N EC25EN, EC25LN, EC30N

1.1

GENERAL INFORMATION

Nameplate and Serial Number Locations

Mast serial number

Chassis serial number Power steering motor serial number

Traction motor serial number Hydraulic motor serial number

Nameplate 8609141

1.2

GENERAL INFORMATION

Dimensions

8609142

8609143

1.3

GENERAL INFORMATION

Dimensions Chart Ref#

Truck Model

EC15N, EC18N

EC20N, EC25N

EC25EN

EC25LN

EC30N

3320 (130)

3340 (131)

3310 (130)

Maximum Lift

Free Lift

115 (4.5)

130 (5.1)

135 (5.3)

Maximum Fork Spacing (outside to outside)

818 (32.0)

Fork Length

1070 (42)

Tilt Angle (forward/backward)

5°/6°

Overall Length

3050 (120)

3155 (124)

3255 (128)

3325 (131)

Overall Width (outside of tires)

945 (37)

1055 (41.5)

1103 (43.5)

Overall Height (to top of mast, lowered)

2105 (83)

2110 (83.5)

Overall Height (to top of overhead guard)

2180 (86)

2210 (87)

Overall Height (to top of mast, extended)

4570 (180)

4550 (179)

Tread (front)

793 (31)

875 (34.5)

900 (35.5)

Tread (rear)

826 (32.5)

900 (35.5)

Wheelbase

1170 (46)

1280 (50.5)

1380 (54.5)

Front Overhang

376 (14.8)

394 (15.5)

406 (16)

Rear Overhang

434 (17.2)

411 (16)

469 (18.5)

Underclearance (at center of wheelbase)

118 (4.6)

124 (4.9)

Unit: mm (in.)

1.4

GENERAL INFORMATION

General Information (Standard Models) Truck Model Units

EC15N

EC18N

meters

3.3

2095

2335

2685

2870

2695

2865

3335

(4620)

(5140)

(5920)

(6330)

(5940)

(6320)

(7353)

3295

3535

4285

4420

4495

4665

5135

(7270)

(7790)

(9470)

(9880)

(9940)

(10320)

(11353)

Standard Controller Without Battery

(standard axle)

With Max.

kg (lb)

Work Performance

Battery

EC25LN

EC30N

kg/mm

1350/600

1600/600

1800/600

2275/600

2500/600

2725/600

Load Center

(lb/in.)

(3000/24)

(3500/24)

(4000/24)

(5000/24)

(5500/24)

(5000/24)

(6000/24)

Maximum Fork Height

mm (in.)

Lift Speed (Rated Load)

33235 (131)

3340 (131)

3315 (131)

36V

m/sec.

.38 (75)

.36 (71)

.32 (63)

.28 (55)

.25 (49)

48V

(fph)

.53 (104)

.49 (96)

.45 (89)

.38 (75)

.36 (71)

Lowering Speed (rated load)

Free Lift

Traveling Performance

EC25EN

Rated Capacity/

.50 (98)

Tilt Angle (forward/backward)

degrees mm (in.)

Travel Speed

36V

km/h

(Without Load)

48V

(mph)

5° / 6° 115 (4.5) 18 (11.2)

17.3 (10.8)

130 (5.1)

135 (5.3)

17.4 (10.8)

17.0 (10.6)

17.1 (10.6)

18.2 (11.3)

Minimum Turning

1790

1840

1990

2045

Radius

(in.)

(70.5)

(72.5)

(78.5)

(80.5)

8.3 (6.2)

36V

60min.

Output

48V

HP(kW)

Transfer

Type

Gear

Ratio

Reduction

Type

Gear

Ratio

Traction Motor

Power Train

EC25N

MHI SX Controller

Standard Simplex Mast Size Service Weight

EC20N

13.7 (10.2)

14.2 (10.6)

17.2 (12.8)

Spur 3.538

3.067 Bevel

4.571

Axle Housing Differential

9.2 (6.8)

12.1 (9.0)

5.0 Banjo

Gear Type/

Gears

Straight Bevel/2

Number

Pinions

Straight Bevel/2

1.5

GENERAL INFORMATION Truck Model

Power Steering System

Units

EC15N

EC18N

Type

EC20N

EC25N

EC25EN

EC25LN

Dynamic Load Sense Inside

83°

54°

56°

Degrees

Turning Angle Outside Steering Wheel Diameter

mm (in.)

328 (13)

kgf/cm2 107 (1522) [10,500] (psi) [kPa]

Cylinder Minimum Test Pressure Type

163 (2320) [16,000]

Self-Adjusting Duo-Servo

Inside Drum mm (in.) Diameter

254

+0 0.13(10.00 +0 0.0051)

Service Brake Brake System

Lining Thickness

mm (in.)

Wheel Cylinder ID

Park Brake

Traveling System

6 (0.24)

Master mm (in.) Cylinder ID

Lever Operating Effort

22.22 (0.8748)

Type

1.6

4.87 (0.19)

28.58 (1.1252)

Mechanical, Mounted on Front Wheels kgf (lbf) [N]

25 to 30 (55 to 66) [245 to 295]

Front Wheels

Fixed Type

Rear Wheels

Center Pivot Type

Mounting

Wheel Alignment

Oscillation Angle Camber

3° Degrees 1°

EC30N

GENERAL INFORMATION Truck Model Units

EC15N

EC18N

EC20N

EC25N

Type Hydraulic Pump

Make Model

Casappa KP20â&#x20AC;&#x201C;24.5

Parker Hydraulics, Inc. 25R029

25 (1.526)

29 (1.77)

Hydraulic System

Make

Interval Valve

9510 Sectional Valve

Relief

kgf /cm2

Pressure

(psi) [kPa]

AUX

158 (2250) [15513]

Lift Tilt

185 (2630) [18133}

Type

Variable

Regulated liter Flow Rate (cu.in.) / min

Lift Cylinders

EC30N

Husco International

Model

Flow Regulator

EC25LN

Gear

Displacement cc (cu in.)

Control Valve

EC25EN

45 (2746)

60 (3661)

45 (1.77)

50 (1.97)

55 (2.17)

63 (2.48)

70 (2.75)

80 (3.15)

8 (4.8)

24 (6.3)

30 (7.9)

mm (in.) Tilt Cylinders

Hydraulic Tank Capacity liter (Approx)

1 (US gal.)

Mast and Forks

Mast Mast Dimensions (Flange Inside Width x THK x WEB THK) Main Rollers

Roller type CL 100 x 42 x 11 (3.94 x 0.59 x 0.47)

115 x 46 x 12 4.53 x 0.79 x 0.51)

Inner

100 x 60 x 10 (3.94 x 0.67 x 0.47)

115 x 45 x 11 (4.53 x 0.83 x 0.51)

Type

#6308 Ball Bearing

#6309 Ball Bearing

Outer mm (in.)

Diameter x Width Side Rollers

Type Diameter x Width

115 x 30 (4.53 x 1.58)

mm (in.)

Forks (Lgth x Wdth x Thk) mm (in.) min/max

42 x 36 (1.65 x 1.42) BL534

BL634

BL834

1070x100x35 (36x4x1.3)

1070 x100 x40 (42 x 3.9 x 1.6)

1070 x 125 x 45 (42 x 5 x 1.8)

240 / 818 (9.4/32)

240 / 920

285 / 960

Voltage

36/48

Battery

Amp Hours (6 hr. rate)

Compartment

Height-Center

Dimensions

Height-Edges

Weight (Min/Max)

115 x 30 (3.94 x 1.18)

Lubricating type needle roller bearing

Lift Chains

Fork Spacing (out to out)

100 x 27 (3.94 x 1.18)

36V

900

1400

48V

700

1100 598 (23.6) 589 (23.2)

mm (in.)

Length

705 (27.8)

Width

903 (35.5) kg (lb)

750/1200 (1650/2650)

772 (30.4)

872 (34.3) 1000 (39.4)

1000/1600 (2200/3550)

1315/1600 (2900/3550)

1400/1800 (3100/4000)

1.7

TABLE OF CONTENTS Chapter 2: Front Axle & Reduction Differential Front Axle Description ................................................................................................................................... 2.1 General Information ................................................................................................................. 2.1 Removal ....................................................................................................................................... Front Wheels ............................................................................................................................ Method 1.............................................................................................................................. Method 2.............................................................................................................................. Method 3..............................................................................................................................

2.2 2.2 2.3 2.3 2.3

2.8 2.8 2.8 2.10 2.10

2.16 2.16 2.16 2.17 2.17 2.18

FRONT AXLE & REDUCTION DIFFERENTIAL

Front Axle Description

5 7

3 2

203658

1. Front wheel hub

5. Reduction pinion

2. Frame support

6. Reduction gear

3. Axle shaft

7. Differential case

4. Axle housing

8. Differential carrier

General Information The frame supports hold the front axle housing in such a manner as to allow a limited amount of rotary motion of the housing, the rotary sliding surfaces being lubricated with grease. The cushion tire is press-fitted to the outer ring of the wheel hub.

2.1

FRONT AXLE & REDUCTION DIFFERENTIAL

Removal Front Wheels

Suggestions

WARNING

Be sure to use the same size and brand tire for replacement.

1. Park the truck on level floor with the parking brake applied, the direction lever in neutral, the forks lowered, and the key switch off. 2. Prepare tools, jacks, and wheel blocks. 3. Block the rear wheels. 4. Loosen the wheel nuts about two turns.

Removal Sequence 2 Wheel nut

1 205952

100902B

1. Wheel Nuts

NOTE

2. Front Wheel

Loosen, but do not remove, the wheel nuts. 5. Raise the front end of the truck. Use one of the methods shown.

WARNING

To prevent possible injury, do not replace the tire when the truck is loaded. Dismount the truck before raising the front tire. To prevent possible personal injury, raise the truck only until the tire just clears the ground. Do not put any portion of your body under the truck. Securely support the truck on blocks after raising it. 2.2

FRONT AXLE & REDUCTION DIFFERENTIAL Method 1

Method 3

Position the jack under the frame and raise the truck until the tire clears the floor.

Fasten a hoist to the mast and lift the front end of the truck as shown.

100828

Jack Capacities

202778A

6. Remove the wheel nuts (loosened in Step 4.)

EC15Nâ&#x20AC;&#x201C;EC18N

3000 kgf (6700 lbf)

EC20Nâ&#x20AC;&#x201C;EC30N

5000 kgf (12,000 lbf)

CAUTION

Be careful not to damage the bolt threads when removing the wheel.

Method 2 Tilt the mast all the way back, place wood blocks under the mast, and tilt the mast forward.

7. Remove the wheel.

CAUTION

After raising the front end, securely support it by blocks.

NOTE Service Limit For Cushion Tires Replace the tire if the height of the solid rubber portion is 25.4 mm (1 in. or less). For tire replacement, consult your Cat lift dealer.

200227

25.4 mm (1 inch)

100880

2.3

FRONT AXLE & REDUCTION DIFFERENTIAL

Installation To install, reverse the removal sequence and do the following steps.

2. Lower the truck until the tire touches the floor. Then tighten the wheel nuts in numbered sequence shown below, in two or three steps, to the specified torque.

CAUTION 1

Use the same size and brand of tire.

6 3

Make sure the clamping surfaces of the wheel nuts and counterbores in the rim are free of dirt. 4 5

1. Install the tire and tighten the wheel nuts. Tighten each nut until its tapered portion is in full-face contact with the counterbore in the rim.

2 205953

Tightening Torque For Wheel Nuts Wheel Nut Counterbore

100835A

2.4

EC15N–EC18N

EC20N–EC30N

16 kgf•m

38.5 kgf•m

(116 lbf•ft)

(278 lbf•ft)

[157 N•m]

[378 N•m]

FRONT AXLE & REDUCTION DIFFERENTIAL

Disassembly 6

205954

Sequence 1. Axle shaft 2. Lock nut, lock washer, oil seal, and tapered roller bearing (inner bearing) 3. Hub & drum assembly [Front wheel hub, brake drum, wheel bolts, drum nuts, and tapered roller bearing (outer bearing)]

4. Tapered roller bearing (outer bearing), oil seal, and oil deflector 5. Tapered roller bearing (inner bearing), and seal retainer 6. Brake assembly 7. Frame support and axle housing

Start By: 1. Remove the mast. (For replacement of the front axle housing and disassembly of the differential, refer to section, MAST AND FORKS.)

3. Support the front end of the truck at both sides with blocks or stands to keep the truck in a horizontal position.

2. Jack up the truck.

4. Remove the front wheels.

NOTE It is not necessary to remove the axle housing or drain the oil for removal of the shaft only.

2.5

FRONT AXLE & REDUCTION DIFFERENTIAL Suggestions

Removing Front Wheel Hub

Removing the Lock Nut

Use a wheel hub puller (Special Tool).

Use a lock nut wrench (Special Tool). Tool Lock Nut Wrench

EC15N–EC18N 91268-00800

Tool

EC20N–EC30N 03703-59001

EC15N–EC18N

Wheel Hub Puller 64309-40100 (Puller seat) (64309-10601)

EC20N–EC30N MH061017

NOTE It is not necessary to remove the oil seal from the hub or to disassemble the oil deflector unless the seal is defective. Special Tool

Any wear or grooves in oil seal deflector would require replacement.

200232

It has been standard practice to replace the oil seal every time the hub is removed to reduce the possibility of oil leaks.

Special Tool

200233

Removing Bearings The inner race of the tapered roller bearing remains in the axle housing when the hub is drawn out. Remove this race together with the seal retainer with a bearing puller.

203651

2.6

FRONT AXLE & REDUCTION DIFFERENTIAL

Inspection after Disassembly Axle Shafts Looseness of Mating Splines

Runout

Mount the differential bevel gear on the splined end of the shaft and set a dial indicator as shown below. Turn the bevel gear and read the indicator.

Set a dial indicator at the middle part of the axle shaft. Turn the shaft and read the indicator to find runout.

Runout of shaft

200235

Free movement (looseness of splines)

0.07 to 0.17 (0.0028 to 0.0067)

0.5 (0.020)

Unit: mm (in.) A = Assembly Standard B = Repair or Service Limit

Axle Housing 1. Check the surfaces of axle housing in contact with the mast bearing for damage. 2. Check the entire axle housing for distortion, dents, and other defects, paying particular attention to the welds to see if any weld is cracked.

Oil Seals and Retainers 1. Check the outer surface of the oil seal retainer for wear or damage.

Face runout of flange

200236

EC15Nâ&#x20AC;&#x201C;EC18N EC20Nâ&#x20AC;&#x201C;EC30N

Runout of axle shaft (1/2 of dial indicator reading

0.5 (0.020) maximum

1.0 (0.039) maximum

1.0 (0.039)

2.0 (0.079)

Unit: mm (in.) A = Assembly Standard B = Repair or Service Limit

Set a dial indicator against the flange of the axle shaft as shown. Turn the shaft and read the indicator to find face runout. Face runout of axle shaft flange

0.05 (0.0020)

0.5 (0.020)

Unit: mm (in.) A = Assembly Standard B = Repair or Service Limit

2. Check the outer and inner oil seals for wear and damage.

2.7

FRONT AXLE & REDUCTION DIFFERENTIAL

Reassembly

Front Wheel Hub

To reassemble, reverse the steps of the disassembly sequence and do the following steps.

1. Fill the front wheel hub, especially the roller holder and oil seal lip groove, with grease. Pack both bearings with grease.

Axle Housing 1. Install the O-ring in the outer groove (of the two grooves in the bore of each frame support). 2. Apply grease to the surfaces A of the support and axle housing. O-ring

Frame support A

205954a

NOTE

200237

Be careful not to apply grease to the brake drum.

Check for excessive movement between frame support and axle housing.

200238

2.8

FRONT AXLE & REDUCTION DIFFERENTIAL 2. Install the inner race and oil seal retainer of the wheel hub bearing with an installer (Special Tool).

Special tool

203569

Tool Installer

EC15N–EC18N 64309-12300

EC20N– EC30N 91468-00300

3. Apply retaining compound to the flange surfaces of the axle shafts.

2.9

FRONT AXLE & REDUCTION DIFFERENTIAL Hub Bearing Preload

Installation and Setting Preload

Tighten the inner nut to produce the required preload. Tighten the outer nut to the specified torque and check the preload. Be sure that the preload noted after tightening the outer nut still meets the specification. This step is for new bearings. Where the bearings removed in disassembly are reused, try to produce the preload at the lower side of the range.

1. Fill the hub with the recommended grease as listed in the service manual.

Preload for hub bearing Tightening torque for lock nuts

5 to 50 kgf•cm (0.4 to 3.6 lbf•ft) [0.5 to 4.9 N•m] 20 kgf•m (145 lbf•ft) [196 N•m]

2. Pack the inner and outer bearing with the recommended grease. 3. Install the inner bearing to the back side of the hub. 4. Install the inner seal. 5. Clean the lining surface of the drum. 6. Install the hub onto the axle. 7. Install the outer bearing, grease seal and preload nut. 8. If the bearings are being reused, try to produce the lower side of the applied force in tangential direction. 9. For new bearings, tighten the preload nut to 14 kgf•m (101 lbf•ft) [137 N•m]. Slowly rotate the hub slightly more than 3 turns, back the nut off 80°, and set the applied force in tangential direction.

Inner nut

Outer nut

200468

10. For models with an outer lock nut, torque the nut to 20 kgf•cm (145 lbf•ft) [196 N•m]. After torquing the lock nut, check the force applied in tangential direction again to insure the preload did not change. Bar

Spring balancer

101653

2.10

FRONT AXLE & REDUCTION DIFFERENTIAL

Reduction Differential Description 3

5 2

1 200240

Sequence 1. Lock plates 2. Side bearing nuts 3. Differential carrier assembly (lock washers, side bearing caps, and differential carrier)

4. Reduction gear and differential gear assembly (spring pins, pinion shafts, differential pinions, differential bevel gear, washers, and differential case) 5. Tapered roller bearings

Start By: 1. Remove the differential carrier from the transmission case. 2. Check the pattern of gears at time of removal. This step is important when assembly has been completed and checking pattern of gears to match.

2.11

FRONT AXLE & REDUCTION DIFFERENTIAL

Disassembly Suggestions

Removing Bearing Inner Races

1. Before removing the differential carrier from the transmission case, measure the gear backlash to aid in obtaining correct backlash at the time of reassembly.

Use a bearing puller to remove the inner races from the differential case.

Backlash between reduction gear 0.15 to 0.25 and pinion (0.0059 to 0.0098) Unit: mm (in.)

200242

200247

2. Put a mark across the bearing cap, adjusting screw and carrier on each side. The caps are not interchangeable.

200241

2.12

FRONT AXLE & REDUCTION DIFFERENTIAL

Inspection after Disassembly Reduction Gear

Differential

Check the teeth for wear, pitting, flaking, or chipping. Minor flaws on the tooth surface can be repaired by grinding with an oil stone or a hand grinder. Check the teeth for contact. If the gear is badly damaged and requires replacement, replace the pinion too. Reduction gear and pinion are a matched set and must be changed at the same time.

1. Check the differential cases for damage. Check in particular the seat formed of each case for carrying the side bearing inner race to see whether the seat surface is galled or not. 2. Check the sliding surfaces of the thrust washers and gears for wear or damage. 3. Check the teeth of the differential pinions and bevel gears for wear, pitting, chipping, or galling. 4. Check the fit of each pinion on the spider. Fit of differential pinions on spider

0.02 to 0.07 (0.0008 to 0.0028)

0.35 (0.0138)

Unit: mm (in.) A = Assembly Standard B = Repair or service limit

2.13

FRONT AXLE & REDUCTION DIFFERENTIAL

Reassembly 4

200243

Sequence 1. Tapered roller bearings

3. Spring pin

2. Differential gear assembly [differential case, thrust washers, bevel gears, pinions, and pinion shaft]

4. Reduction gear

2.14

5. Differential carrier assembly [carrier, side bearing caps, side bearing nuts, and lock washers]

FRONT AXLE & REDUCTION DIFFERENTIAL Suggestions Reassembling Differential Pinions

Reassembling Differential Case

The thrust washers of the differential gears are to be used for adjusting the backlash between the differential gears and pinions. Measure the backlash and, if it exceeds the limit, replace the thrust washers.

After putting the case assembly in place on the carrier, install the bearing caps tentatively by making the cap bolts snug tight. The caps are to be secured tight after the bearing preload has been adjusted.

Backlash between differential gears and pinions

0.18 to 0.23 (0.0071 to 0.0091)

0.5 (0.020)

Unit: mm (in.) A = Assembly Standard B = Repair or service limit

Installing Bearing Caps Be sure to know which are the left and right caps and to put each cap in place correctly. Tightening torque for bearing cap bolts

12.8 kgf•m (93 lbf•ft) [126 N•m]

200244 200241

Installing Reduction Gear Apply LOCTITE No. 271 to the bolts for holding the reduction gear to the case. Be sure to tighten these bolts evenly so as not to strain the gear. Tightening torque for reduction gear bolts

12.0 kgf•m (87 lbf•ft) [118 N•m]

2.15

FRONT AXLE & REDUCTION DIFFERENTIAL

Inspection and Adjustment Side Bearing Preload

Reduction Gear Backlash

Tie a wire on the reduction gear tooth and hook a spring scale to the wire. Tighten the side bearing nuts while reading the spring scale until the specified preload is obtained.

Adjust the backlash between the reduction gear and pinion after installing the differential carrier assembly to the transmission case. To measure the backlash, set a dial indicator with its spindle pointing squarely to the tooth face of the reduction gear. With the pinion held, move the gear back and forth to read the indicator. Adjust the backlash using the left and right side bearing nuts and pinion shims.

NOTE Before measuring the preload, tap the back of the reduction gear with a copper hammer while rotating the gear to center between bearing.

Preload for differential case side bearings

Min.

15 to 30 kgf (1.1 to 2.2 lbf) [1.5 to 2.9 N]

Max.

1.32 to 2.5 kgf•cm (2.9 to 5.5 lbf•ft) [13 to 25 N•m]

Backlash between reduction gear and pinion

0.15 to 0.25 (0.0059 to 0.0098) Unit: mm (in.)

As force applied to reduction gear in tangential direction.

200247

Backlash Increase Decrease Decrease

200246

Increase Increase Backlash

Decrease 200248

2.16

FRONT AXLE & REDUCTION DIFFERENTIAL Reduction Gear Face Runout

Tooth Contact

Using a dial indicator, check the reduction gear for face runout at the maximum radius position in back of the gear. If the runout exceeds the limit, check the reduction gear bolts for tightness; retighten if necessary. Check the tapered roller bearings for condition. Readjust or replace them if necessary.

Check the gear reduction tooth contact. To check, apply a thin coat of bluing to several gear teeth on both drive and coast sides. Press forward on the reduction pinion and rotate the reduction gear back and forth until a contact pattern is noted on both concave and convex faces of the gear teeth. To adjust the tooth contact, refer to the chart.

Face runout of reduction gear

0.05 (0.0020) maximum

Unit: mm (in.) A = Assembly Standard B = Repair or Service Limit

200250

200249

2.17

FRONT AXLE & REDUCTION DIFFERENTIAL Tooth Contact Adjustment (EC15Nâ&#x20AC;&#x201C;EC18N) Tooth Contact

Adjustment

Extends from toe to middle portion, covering not less than 50% of tooth length.

Correct tooth contact

203669-1

1. Move gear away from pinion.

Short contact at toe of tooth.

2. Move pinion toward gear by increasing shim thickness to secure correct backlash.

2 203669-2A

203669-2

1. Move gear toward pinion.

Short contact at heel of tooth.

2. Move pinion away from gear by decreasing shim thickness to secure correct backlash.

3 203669-3A

203669-3

1. Move pinion toward gear by increasing shim thickness.

Heavy contact on face or upper portion of tooth.

2. Move gear away from pinion to secure correct backlash. 203670-4A

203669-4

1. Move pinion away from gear by decreasing shim thickness.

Heavy contact on flank or lower portion of tooth.

5 203669-5

2. Move gear toward pinion to secure correct backlash. 203670-5A

Repeat the above adjustment until the correct tooth contact is obtained.

2.18

FRONT AXLE & REDUCTION DIFFERENTIAL Tooth Contact Adjustment (EC20Nâ&#x20AC;&#x201C;EC30N) Tooth Contact

Adjustment

Extends from toe to middle portion, covering not less than 50% of tooth length.

Correct tooth contact

203670-1

1. Move pinion toward gear by increasing shim thickness.

Short contact at toe of tooth.

2. Move gear away from pinion to secure correct backlash.

2 203670-2A

203670-2

1. Move pinion away from gear by decreasing shim thickness.

Short contact at heel of tooth.

2. Move gear toward pinion to secure correct backlash.

3 203670-3A

203670-3

1. Move pinion toward gear by increasing shim thickness.

Heavy contact on face or upper portion of tooth.

2. Move gear away from pinion to secure correct backlash. 203670-4A

203670-4

1. Move pinion away from gear by decreasing shim thickness.

Heavy contact on flank or lower portion of tooth.

5 203670-5

2. Move gear toward pinion to secure correct backlash. 203670-5A

Repeat the above adjustment until the correct tooth contact is obtained.

2.19

TRANSFER ASSEMBLY

Front axle center

Description 1

Traction motor

7 5

209002

Main component 1 2 3 4 5

6 7 8 9

Transfer case Transfer cover Input gear (13T) Output gear (48T) Bevel gear set

Taper roller bearing Lock nut Ball bearing Plug (standard) or pulse generator (option)

The transfer assemblies of all the 1 ton, 2 ton, and 3 ton class trucks share completely identical components except the different bevel gear sets as shown below. No. of teeth on bevel pinion

No. of teeth on bevel gear

1 ton class trucks

2 and 3 ton class trucks

3.1

TRANSFER ASSEMBLY

Disassembly Start by: (1) Remove the drain plug on the front axle housing to let the oil drain out.

(3) Remove the traction motor, reduction and differential assembly and transfer assembly as one unit, from the front axle housing.

(2) Disconnect the connectors of the traction motor harnesses and pulse generator harness.

(4) Separate the three assemblies removed in step (3) from each other.

Liquid gasket

14 17 Plug (standard) or Pluse generator (option)

Staked 7

4 6

9 13

12 209002A

Disassembly sequence 1 Bolt 2 Transfer cover 3 Side cover with pulse generator, or plug 4 Nut 5 Shim Remove parts 6 and 8 as a unit. 6 Bevel pinion shaft 7 Shim 8 Bearing cone 9 Bearing cone

3.2

10 Output gear 11 Spacer 12 Bearing cup 13 Bearing cup 14 Snap ring Remove parts 15 to 17 as a unit. 15 Input gear 16 Ball bearing 17 Ball bearing 18 Transfer case

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