Chapter I Basic Knowledge of HW Transmission

Requirements:
Comprehend the function and model of transmission, the features of structure of twin countershaft
transmission and Structure of Planetary Gear Transmission. Grasp the feature and advantage of
HW series transmission, as well as its position at home and abroad.

Section I Cognizing of Transmission

I. Transmission Position

Master Different
Clutch Universal joint
Transmission reducer

Drive axle
Drive axle housing
Half axle

II. Functions of Transmission

Drive from the engine passes to the transmission by clutch, and then is altered to suitable ration by
transmission to drive axle, master reducer, different, half axle to the vehicle drive wheel in the
automobile drive system. Transmission play an important role in the vehicle drive system, and its
function can directly affect the driver’s comfort and operation.
Main functions of automobile transmission:
a) Alter the transmission ratio, enlarge the changing ranges of drive wheel torque and speed to
fit the often changing driving conditions and at the same time, make the engine running
under the best conditions (higher power and lower oil consumption).
b) Make the automobile to reverse driving under the condition that the engine does not change
its turning direction.
c) Make the engine start, idle and be convent to shift gear by using neutral position to breakout
the power transferring.

III. Classification of Transmission

1. Manual Transmission(MT)
Manual Transmission (MT) is the most normal transmission, which is composed by gear
and axle and can meet the purpose of changing speed and torque by engaging different
gears.
2. Automatic Transmission (AT)
Automatic Transmission (AT) is composed by hydraulic torque-converter, planet gear,
hydraulic operation system, and changes the speed and torque by hydraulic transferring and
gear combination. It can automatically change the shift gear by the position of accelerator
pedal and driving speed change, and the driver only need to operate the accelerator pedal
and braking pedal to control the automobile speed. Although there is not operating clutch in
the automatic transmission vehicle, there are lots of clutches in the automatic transmission.
All these clutches can automatically separate or close with the speed changing to realize the
purpose of automatic speed changing.
3. Automated Mechanical Transmission (AMT)
Automated Mechanical Transmission (AMT) is also called Electronic Control Mechanical
Automatic Transmission. This transmission does not change the main structure of traditional
manual transmission; its key technology is digital shift gear structure controlled by a set of
Electronic Control Unit (EUC). Its basic principles is, recurring by the related executive
structures (oil supporting, chosen shift gear, clutch joint and split), integrated operation to
the engine, clutch, and transmission of vehicle power drive system to realize the starting,
gear shifting and automatic operation according to the driver intentions (accelerator pedal,
braking pedal) and the vehicle situations (engine speed, output shaft speed, vehicle speed,
and shift gear and others), and by a certain rules ( shift gear, clutch joint and split and
others).
4. Continuously Variable Transmission (CVT)
Continuously Variable Transmission (CVT) is only adopted two sets of belt pulley to carry
on variable transmission, which is the most difference from the ordinary automatic gear
transmission which used the complex and heavy gear assembly to variable transmission.
This transmission carries on the speed changing by alteration the contact radius of the
driving wheel and the driven wheel. The pulley is usually made of rubber belt, metal belt,
metal chain and others. Its advantages are lighter heavy, smaller volume, fewer parts and
higher efficiency and lower oil consumption compared with the Automatic Transmission.
However, its disadvantages are distinct, that is the drive belt easier damage or slip, and not
bearing the heavier load.
5. Dual Clutch Transmission (DCT)
Dual Clutch Transmission (DCT), based on the manual transmission but not the automatic
transmission, is different from the ordinary automatic transmission system, and can offer
continuous power output except the flexibility of the manual transmission and comfort of
the automatic transmission. While the traditional manual transmission, adopting one set of
clutch, can lead the power output to be broken by power gap during gear shifting period
when the driver stamp the clutch pedal and change another shift gear by hand.
DCT，equipped with two automatic control clutches, can control two clutches operation by
electronic controlling and hydraulic pressure pushing. When transmission operating, one set
gear engaged; however, when shift gear is closed, next set gear has been pre-elected and this
clutch is still in the split. When gear shifting, one clutch separates the engaged gear, another
clutch has been pre-elected and this ensure to keep at least one set of gear to output power
during the gear shifting period and no power output breaking occurring. In order to
cooperate with the above-mentioned operation, movement of DCT drive axle is divided to
two parts, one is solid drive axle, and another is hollow axle. The solid drive shift connects
to the one, three, and five-shift gear, and the hollow drive axle connects to the two, four,
six-shift gear. Each clutch takes charge of one engaged action of a drive axle, and power of
the engine can be continuous transmitted by one of the drive axle.
DCT, based on the manual transmission and special design, can resist 350 N.M torque; and
due to the exact computer operation, it posses more precise gear shift controlling compared
with ordinary manual transmission. So, DCT can also become less oil consumption
transmission system. Based on the feature and operation model, DCT system can bring the
 driver a feeling of racing car driving. In addition, it eliminates the power broken of manual
transmission during gear shifting, and makes more comfortable driving.

Section II HW Series Transmission Features

I. Revelation of HW Series Transmission.

Sino-truck, in order to adapt to the developing trend and matching demand of greater power of
heavy truck, independently develop HW series new transmission assembly for different working
and road conditions technological innovation, depending on the strong research and developing
strength and several years’ technological accumulation, as well as collecting the great
achievements of transmission of the world. At present, there are six series:
HW18709、HW20716、HW18710、HW14710、HW18712、AMT, have been developed, as shown
in Figure 1-1.

Figure 1-1: Shape of HW Series Transmission

II. Main Structure Features and Advantages of HW Series Transmission.

1. Main gear-box adopts a twin countershaft structure, and supplementary gear-box
adopts planetary gear drive structure. This greatly upgrades the reliability of
assembly.

Figure 1-2: Drive Structure of HW Series Transmission

 Main gearbox is twin countershaft structure, which can distribute the power. Each
countershaft, two end bearings and gears of countershaft only bears 1/2 general power, and
the input shaft and gears of the spindle bears 1/2 general powers too. So, the spindle bears
the same power which is in opposite direction, and only bears the torque, not bending
moment. This design eliminates destroy to the engaged area caused by the spindle
deforming, reduces the noise of gear engagement of transmission and increases the
longevity of the gears. By these means, the transmission can prolong its use life and make it
more stability and reliability.
The twin countershaft, by reducing the center distance, diameter of each shift gear, width of
gear and diameter of each axle, can shorten the dimension of transmission axles, lighten the
weight. Short dimension is convent for arrangement of whole vehicle, and light
transmission weigh can reduce the oil consumption, then the economic benefits can be
increased.
Supplementary gearbox is planet gear drive structure, which effective overcomes the
problem of pre-malfunction of supplementary gearbox (especially used in the worse
conditions, such as mine industry and others, its effect is more distinctness), and greatly
prolongs the use life of transmission assembly based on the sufficient analysis of
malfunction model of supplementary gearbox by using twin countershaft and overcome this
defect.
2. Main gearbox adopts two-stage floats, and supplementary gearbox adopts center
wheel float. This can ensure each gear even load.
Both end of the spindle have float amount and gear float of spindle; this can ensure the load
to be distributed evenly. Sun wheel and gear float of supplementary gearbox ensures the
planet structure to be loaded evenly. The structure, connected the twin countershaft of main
gearbox with the supplementary gearbox, needs special positioning device of spindle as the
following figure shown.

1. spindle，2. bush，3. ball joint，4. output shaft，5. bearing，6. input shaft

Figure 1-3: Float of Spindle and Planet Structure

3. Input shaft adopts Span Support Structure to increase the support rigidity, and the
reliability of supplementary gearbox.
Rigidity support of big span bearing of output shaft ensures the support rigidity of output
shaft, and it increases the life of gear and synchronizer of supplementary gearbox, and
effectively resolves the disadvantage of short life of other products.
4. The Gear Shifting between main gearbox and supplementary one, has mutual
interlocking gear, this effectively protect the synchronizer of supplementary gearbox.
 Figure 1-4: Interlocking Gear of main and supplementary gearboxes

The synchronizing ring of synchronizer of supplementary gearbox, which is made by

Molybdenum sprayed on steel base, has features of larger friction force and longer use life.
Additional main and supplementary gearboxes can ensure that before the supplementary
gearbox shifting gear, the main gearbox can do this. This can greatly prolong the use life of
synchronizer of supplementary gearbox.
When range gear fork axle of supplementary gearbox does not get position, the interlocking
plate is exactly inside of the groove of fork axle of main gearbox by the spring operation,
and then the fork axle of main gearbox is locked in the neutral position. When range gear
fork axle of supplementary gearbox gets position, it can push the interlocking turning to
unlock the control of fork axle of main gearbox, and then the driver can put into gear on
demanding.
5. The Housing of Transmission Adopts Vertically-split Structure which is Convenient to
assemble and maintain.
The main housing adopts vertically-split structure. The dimension of the middle part of the
housing can be adjusted in accordance with the volume and shift gears of the transmission,
and another two parts can be in common use. In addition, the vertically-split structure
makes the gear alignment easily and rapidly.

Figure 1-5: The Housing Structure of HW Series Transmission

6. Design of Small Functional Integrated Cover makes the Assembly Structure
Compaction.

Figure 1-6: Structure of Small housing Assembly of HW Transmission

Shift gear swing-arm, shift gear head, interlocking fork, sensor drive ring, sector lock block,
high and low shift gear locating ring, all are equipped in the gear axle. The gear shift choice
can be realized by gear axle horizontal movement through swing-arm operation, and putting
into gear and out of gear can be realized by gear axle front and back movement. Shift gear
interlocking function, which can avoid the random gear, can be realized by interlocking
fork. Shift gear locking, which can avoid gear escaping, can be realized by lock device. All
functions of the locking, interlocking and shift gear choice are centralized in the small
housing, it can make the function more reliability and maintenance more convenience.
7. Initiative Lubricating Adoption.
The key parts of HW series transmission adopt initiative lubricating. Adding lubrication oil
pump and relative oil pipe in the transmission assembly can greatly prolong the use life of
transmission.

Figure 1-7: Lubricating System of HW Series Transmission

8. Power Take-off (PTO) Output with Direction invariable and Convenient PTO for
Braking and Travelling.

Figure 1-8: PTO Installment of HW Series Transmission

PTO is driven by right auxiliary axle of main gearbox; its direction and speed are not
affected under this condition. This can be convenient to realize power take-off in neutral
position, and ensure normal direction turning under the reverse shift gear conditions.
9. Greatly Increasing the Reliability of Dual H Valve by its Cut-off Structure Design
Dual H valve assembly in the HW transmission adopts end seal, and greatly increases its
reliability.

Figure 1-9: Dual H Valve Assembly of HW Series Transmission

10. Range Shift Gear Fork Adopts Swing-fork Design, and Fork Axle Adopts Span
Support Structure, all these increase the use life of shift gear structure.
This kind of design can effectively reduce the bending moment of range shift gear fork and
fork axle, improve the interaction of the shift gear axle and hole of housing, and increase the
relevant use life and reliability.

Figure 1-10: Shift Structure of HW Series Transmission

Section III Comparing HW Series Transmission with Another

I. Comparing with All Structures of Transmission.

The structure of main gearbox of transmission has single countershaft and twin countershaft
structures, such as the ordinary structure of ZF Series Transmission is single countershaft
structure, the ordinary structure of Fuller transmission is twin countershaft structure. The structure
of back supplementary gearbox of transmission has twin countershaft structure and planet drive
gear structure, such as the ordinary structure of ZF series transmission is planet drive gear
structure and the ordinary structure of Fuller series is twin countershaft structure.
1. Comparing Single Countershaft Structure with Twin Countershaft Structure.
The ordinary parts of transmission is gear, which is extensively applied in all kinds of
mechanical products due to advantages of its smaller volume, lighter weight, invariable
drive ratio, stable working and larger drive power. Involute gear, easily manufactured and
inspected, suitable for scale production, is ordinary transferring parts of transmission.
20°pressure angle, which comprehensive performance is best, is often used in Involute gear.
During gear driving period, the gear bears tangent force and radial force at the same time,
its ratio is 2.75 (20°pressure angle). Suppose drive torque is 1000 Nm, center distance of
gear is 150mm, and the drive ratio is i, then it bears 2424 (i +1) radial force. The more
radial force, the more bending deformation of gear axle and that worsens the engagement
condition.
The principle of twin countershaft structure is that the inputting power, from input shaft, is
divided into the two countershafts by drive gear, then influxes to the output shaft.
Theoretically, because each countershaft only transfers 1/2 torque, the transmission, adopted
 twin countershaft structure, can reduce the thickness and center distance of gear, shorten the
whole length of axle, and lighten the weight of whole transmission. Twin countershaft
structure, in order to meet the correct engagement and try to distribute the load evenly,
eliminates needle bearing in the hole of spindle gear of single countershaft structure by
spindle gear radial floating in the spindle. During working, the force, imposed to the spindle
gear by the two countershaft gears, is equal and direction opposite. So, the spindle only
bears torque and does not bear bending moment. This improves the force bearing condition
of spindle and bearing, and greatly increases the reliability of transmission.
Twin countershaft structure, in order to resolve the correct engagement of spindle gear and
countershaft gear, must be carried on gear alignment, which increases the manufacturing
difficulty, by correct locating of the countershaft gear in the countershaft. Therefore,
application twin countershaft structure in the transmission assemble with smaller input
torque is not suitable for its high manufacturing cost and not playing its advantage role.
2. Comparing Twin Countershaft Structure with Planet Drive Gear Structure in back
supplementary gearbox of Transmission.
From above-mentioned analysis, we can see that twin countershaft structure reduces the
transferring torque of each gear, and increases drive application performance. Back
supplementary gearbox, usually used as range shift gear supplementary gearbox, has large
gear difference due to drive ratio is less 3, and only two pairs of gear engagement. Input
torque of back supplementary gearbox of transmission is four times of input torque of
transmission. The more input torque of transmission, the more force bearing of
supplementary gearbox of twin countershaft, and the more possibility of malfunction. The
exhibition of twin countershaft supplementary of transmission in heavy car applied under
worse working condition also proof this point. The main malfunction is gear broken, crush,
and pit corrosion, housing crack of supplementary gearbox and short use life of
synchronizer.
The planet drive gear is composed by one sun wheel, five planet wheel, and one inner gear
ring. Theoretically, each planet wheel only transfers 1/5 torque, and force bearing condition
of gear is greatly improved and application reliability and life of back supplementary
gearbox of transmission is increased due to output shaft is supported in the large span axle.
When supplementary gearbox is in the high shift position, there is not gear engagement
drive among planet drive structure, so the drive ratio can arrive 100%. This is benefit for
saving oil.
From above-mentioned analysis we can see that with input torque increasing and under the
limited structure condition, main gearbox adopts the drive is from single countershaft to
twin countershaft; supplementary gearbox adopt the drive is from twin countershaft to
planet drive gear structure. HW series transmission, made by Sinotruck, is more suitable for
larger power, large torque, worse road condition, and for increasing the use life of assembly.
II. Developing Tendency of Heavy Truck Transmission
With energy crisis intensified, more and more strict requirement of environment protection all
over the world, the general developing tendency of world heavy truck is higher power, lower oil
consumption, and lower noise. In order to effectively increase the whole vehicle power and
sufficiently play the role of advantages of high efficiency and rapidness of the transportation of
heavy truck, the engine of this vehicle is required to equip with larger horsepower, lower rev and
greater torque to reduce the emission, environment pollution and to meet Europe three or even
more higher emission standard. At the same time, the transmission is required multi-shift gear,
larger torque (over 1500 Nm), larger rev ratio, higher efficiency and lower noise.
In recent years, ZF Company has manufactured ZF—New Ecosplit and ZF ASTronic series
transmission of heavy truck.
ZF New Ecosplit is manual transmission with 1600-2700 Nm torque; it is a successful production
of mechanical transmission of heavy truck of present ZF Company.
ZF ASTronic series transmission is full automatic mechanic transmission (AMT), developed by
ZF Company in recent years for equipment with heavy truck. Its largest torque is 2600 Nm. Its
whole structure is twin countershaft plus planet drive gear system, composed by insert shift
structure, basic main gearbox structure, range shift structure. It is first time that ZF Company
altered the design of the traditional single countershaft full synchronizer. Its insert shift and main
gearbox adopts twin countershaft drive, and the main gearbox has not equipped with synchronizer,
but adopts slip gear shift. ZF ASTronic series transmission is in the leader position of the world.
Eaton Corp, which main market in North America, manufactures twin countershaft series
transmission of heavy truck. Based on the Fuller RT-11509, and after a series technological
innovation, it designed a series transmission assembly of heavy truck. Eaton Corp is the more
important transmission manufacturing company in the world.
Chinese transmission technology of heavy truck mostly comes from America, Germany, Japan,
and others. The introduced technologies mostly belong to the products of 80s-90s of twenty
century. During the long introducing and digesting period, a series new product has been
developed by us through model changing. However, this developing is a common one; there is not
real key technological product.
Sinotruck
Twin countershaft + planet wheel
structure

Domestic factory

Twin countershaft structure

Domestic factory
Single countershaft + planet wheel
structure

Figure 1-11: Comparing Transmission of Heavy Truck

Green: common level of domestic factory.
Yellow: few domestic factories can meet the level; it must be paid high cost and the quality is difficulty to ensure.
Red: domestic factory hardly meet the level; it must be gained by long time technological innovation, paid high
cost, but the foreign advanced enterprise can arrive this level.

From above figure we can see that the largest torque of domestic transmission, made by domestic
factory which adopted single countershaft plus planet wheel structure, is very difficult to over
1000 Nm. But the largest torque of domestic transmission, made by domestic factory which
adopted twin countershaft structure, can arrive at 1500 Nm. Therefore, the factory which adopted
twin countershaft structure has relatively advantage in domestic transmission market of heavy
truck. But with China heavy truck walks up to internationalization, this advantage will be lost. The
largest input of HW series transmission, independently developed by Sinotruck, can arrive at 2000
Nm, and will be 2500 Nm after technological innovation. Therefore, it will posses absolutely
advantage in the domestic market of transmission of heavy truck.
Furthermore，the structure of HW series transmission has lots similarities with the ZF ASTronic
series, and adopted some special mechanism (have been applied patent). All theses explained that
the independent design capability of Sinotruck is arriving at the world advanced level. The special
structure of HW transmission can easily translate into automatic mechanical transmission (have
realized). This is perfect combination of world advanced technology and Chinese present
manufacturing level, and can support the top transmission of heavy truck for domestic consumer.
Important Points of This Chapter:
What the function of the automobile transmission and what the transmission classification is. The
structure features and advantages of HW series transmission. The structure features of twin
countershaft structure and planet drive gear structure. What the position of HW series transmission
is.

Exercises:
1. How many functions of automobile transmission?
2. How many main classifications of automobile transmission?
3. The structure features and advantages of HW series transmission.
4. What advantage of interlocking device between main gearbox and supplementary gearbox
of HW series transmission.
5. How many functions of small housing assembly of HW series transmission?
6. How to realize the PTO of neutral position of HW series transmission?
7. The principle of twin countershaft structure.
8. What advantage and disadvantage of comparing single countershaft structure with twin
countershaft structure.
9. What advantage of comparing planet drive gear structure and twin countershaft structure.
10. HW series transmission how to ensure that before the synchronizer of supplementary
gearbox finished transferring, the main gearbox can’t change shift.
11. Narrate developing tendency of heavy truck.
12. Narrate the position of HW series transmission.
 Chapter II Principle of HW Series Transmission

Requirements：
Grasp structure principle of HW series transmission and shift figures of drive route.

Section I Structure of HW Series Transmission

I. Drive Structure of HW Series Transmission.

Main gearbox of HW series transmission adopts twin countershaft structure, the two countershafts
have 180° angle; the supplementary gearbox adopts planet drive gear structure. Inputting power
from input shaft is divided into the two countershafts, then influxes into the spindle, finally output
by planet drive gear of supplementary gearbox to realize the power transferring.

1. HW18709 Series Transmission

HW18709 series transmission is composed by main gearbox, two-section supplementary

gearbox. Main gearbox has five forward shifts, and the supplementary gearbox has two
shifts, so there are nine (4 x 2 + 1) forward shift and one reverse shift. The main drive
structure is as shown in figure 2-1:

Main gearbox is manual operation and supplementary gearbox is air operation. Operation
and controlling devices of HW 18709 series transmission have styles of single lever dual H
shift device and double lever dual H shift device.
 Figure 2-1: Main Drive Structure of HW18709、HW18710 Series Transmission

2. HW20716 Series Transmission

HW 20716 series transmission composed by front supplementary gearbox, main gearbox

and back supplementary gearbox. There are eight forward shifts, including four shifts of
main gearbox and two of supplementary gearbox. There are totally sixteen (2 x 4 x 2)
forward shifts and two reverse shifts after front located insert fork split. The structure of
main drive is as shown in Figure 2-2.

Main transmission is manual operation and front and back supplementary transmission is air
operation. Shift operation and controlling structures of HW 20716 series transmission has
two style of single lever double H shift device directly controlled by air valve and
double lever double H shift device directly controlled by air valve.

3. HW18710 and HW14710 Series Transmission

HW18710 and HW14710 Series Transmission are composed by main gearbox, two-section
supplementary gearbox. There are totally 10 forward shifts (5 x 2) and 1 reverse shift,
including 5 shifts of main gearbox and 2 of supplementary gearbox. The main drive
structure is as shown in Figure 2-1.

Shift operation and controlling of HW18710 and HW14710 Series Transmission has two
styles of single lever double H shift device directly controlled by air valve and double
lever double H shift device directly controlled by air valve.

Figure 2-2: Structure of HW20716 Series Transmission

II. Control Structure of HW Series Transmission

1. HW18709 and HW20716 Series Transmission

The control structure of HW18709 and HW20716 Series Transmission is as shown in

Figure 2-3. High and low shift locating ring and shift head is settled on the shift axle. High
and low shift locating spring, centering spring and others makes up the shift lock and
formed 5 clear shift positions. These five positions parallelize five positions of shift head;
each position can swing front and back to form two shifts. Shift head adopts double head
structure, which can be dialed one same axle in two different positions. At the same time,
axle movement of shift axle can drive along the interlocking fork to drive double H
assembly to realize the range shift to change. Main gearbox shift cooperates with range shift
to realize 9 shifts of HW 20716 and 10 shifts of HW 18709. Control structure of HW20716,
cooperated with air directly control insert fork, can realize 16 forward shifts and 2 reverse
shifts.

1—shift swing arm 2—dustproof cover 3—shift axle 4—sensor drive ring
5—pressure switcher of reverse shift 6—shift head 7—interlocking fork 8—centering spring
9—range shift lock pin 10—high and low shift locating ring 11—centering spring
12—end cover of small housing 14—drive pin 15—sector lock block
16—pressure switcher of neutral position 17—lock pin axle 18—double H valve assembly
19—lock spring 20—small cover housing
Figure 2-3: Control Structure of HW 18709 and HW 20716 Series Transmission

Interlocking fork, shift head, fork axle block unite and compose shift interlocking structure.
The shift head is opposite to the two grooves of interlocking fork. Only when the fork block
directly opposite to the groove of the interlocking fork, the fork block can be pulled out to
realize shift. If shift head is not opposite to the groove of the interlocking, the fork block
can’t be pulled out of the interlocking, and then can’t realize to shift. This ensures that shift
 can only be changed in the five clear shift positions to realize reliable interlocking function.

Sector lock block, lock pin axle, lock spring and others unites and composes the lock
structure which ensures the reliability of locking.

The smaller housing, on which the shift choice, shift, locking, interlocking, and signal drive
are perfectly organized, makes all kinds of functions more reliability and much easily
maintenance.

2. HW18710 and HW14710 Series Transmission

Figure 2-4: Control Structure of HW18710 and HW14710 Series Transmission

The control structure of HW18710 and HW14710 Series Transmission is as shown in

Figure 2-4. Centering spring and centering seat ring are settled on the shift axle, which
unites and composes shift lock with small housing hull and spacer ring to form 3 clear shift
positions. These 3 positions parallelize 3 positions of shift head; each position can swing
front and back to form two shifts. Control structure of HW18710 and HW14710 cooperates
with air directly control insert fork, can realize 10 forward shifts and 2 reverse shifts.

Interlocking fork, shift head, fork axle block unite and compose shift interlocking structure.
The shift head is opposite to the two grooves of interlocking fork. Only when the fork block
directly opposite to the groove of the interlocking fork, the fork block can be pulled out to
realize shift. If shift head is not opposite to the groove of the interlocking, the fork block
can’t be pulled out of the interlocking, and then can’t realize to shift. This ensures that shift
can only be changed in the three clear shift positions to realize reliable interlocking
function.

Sector lock block, lock pin axle, lock spring unites and composes the lock structure which
ensures the reliability of locking.
 Section II Drive Route and Shift Figure of HW Series Transmission

I. Drive Route of HW Series Transmission.

1. Drive Route of HW 18709 Series Transmission is as shown in Figure 2-5.
creep shaft gear
1-shift gear

2-shift gear

3-shift gear

4-shift gear

5-shift gear

6-shift gear

7-shift gear

8-shift gear

Reverse shift gear

Figure 2-5: Drive Route of HW18709 Series Transmission

2. Drive Route of HW18710 and HW14710 is as shown in Figure 2-6.

1-shift gear

2-shift gear

3-shift gear

4-shift gear

5-shift gear

6-shift gear

7-shift gear

8-shift gear

9- shift gear

10- shift gear

Reverse shift gear

Figure 2-6: Drive Route of HW18710 and HW14710 Series Transmission

3. Drive Route of HW20716 Series Transmission is as shown in Figure 2-7

1-shift gear

1-shift gear
2-shift gear

2-shift gear
3-shift gear
3-shift gear

4-shift gear
4-shift gear
5- shift gear

5- shift gear
6- shift gear
6- shift gear

7- shift gear

7- shift gear
8- shift gear
8- shift gear
Reverse shift gear

Reverse shift gear

Figure 2-7: Drive Route of HW20716 Series Transmission

II. Shift Figures of HW Series Transmission

Shift Figure of HW18709 Series Transmission Shift Figure of HW14710 Series Transmission

Shift Figure of HW20716 Series Transmission

 Section III Main Technological Parameters of HW Series
Transmission

I. Nameplate of HW Series Transmission

Figure 1-8: Nameplate of HW Series Transmission

Model: numbered rules as follow:

HW 18 7 10 A X -S

Forward shift
Series number, heavy transmission series
1/10 1% torque, adopts 1/10 when less than three digitals.
Brand.
A-AMT；X- overdrive；S- Synchronizer……
Customer No.: such as HW18709 071011

Design series No.

Model of HW transmission assembly.
Series No.: mark specified by the enterprise to only identify the transmission assembly.

II. Major performance Parameters of HW Series Transmission

1. Main Technological Parameters of HW 18708 Series Transmission
Model HW18709 Installation length 843
Style 9 forward shifts,1 reverse shift (three-section shell)
The largest input torque 1800N•M Largest input rev. 2600rpm
Speed ratio of each shift Shift position Speed ratio Shift position Speed ratio
creep shift 12.68 5-shift gear 2.5
1-shidr gear 8.46 6-shift gear 1.85
2-shift gear 6.26 7-shift gear 1.37
 3-shift gear 4.64 8-shift gear 1
4-shift gear 3.38 Reverse shift 11.63
Main gearbox is splash lubrication and supplementary gearbox is
Lubrication method
forced lubrication
Lubrication brand 85W/90 GL-4 or 85W/90 GL-5
Fuel charge 12L(with PTO is 12.5L)

2. Main Technological Parameters of HW 20716 Series Transmission

Model HW20716 Installation length 915
Style 16 forward shift,2 reverse shift (three-section shell)
The largest input 2600rpm
2000N•M Largest input rev.
torque
Shift Speed ratio Speed ratio Shift Speed ratio Speed
positions (L) (H) positions (L) ratio(H)
1-shidr gear 15.59 13.13 6-shift gear 2.49 2.10
Speed ratio of 2-shift gear 10.89 9.17 7-shift gear 1.71 1.44
each shift 3-shift gear 7.48 6.30 8-shift gear 1.19 1.00
4.38 Reverse 14.29 12.03
4-shift gear 5.20
shift
5-shift gear 3.56 3.00
Lubrication Main gearbox is splash lubrication and supplementary gearbox is
method forced lubrication
Lubrication
85W/90 GL-4 or 85W/90 GL-5
brand
Fuel charge 13L(with PTO is 13.5L)
3. Main Technological Parameters of HW 18710 Series Transmission
The First Series
Model HW18710 Installation length 843
Style 10 forward shift,1 reverse shift (three-section shell)
The largest input torque 1800N•M Largest input rev. 2600rpm
Shift position Speed ratio Shift position Speed ratio
1-shidr gear 14.58 6-shift gear 3.33
2-shift gear 10.94 7-shift gear 2.5
Speed ratio of each
3-shift gear 8.1 8-shift gear 1.85
shift
4-shift gear 6 9-shift gear 1.37
5-shift gear 4.375 10-shift gear 1.00
Reverse shift speed ratio 15.04 3.44
Main gearbox is splash lubrication and supplementary
Lubrication method
gearbox is forced lubrication
Lubrication brand 85W/90 GL-4 or 85W/90 GL-5
Fuel charge 12L(with PTO is 12.5L)

The Second Series

Model HW18710 Installation length 843
Style 10 forward shift,1 reverse shift (three-section shell)
The largest input torque 1800N•M Largest input rev. 2600rpm
Shift position Speed ratio Shift position Speed ratio
1-shidr gear 14.28 6-shift gear 3.27
2-shift gear 10.62 7-shift gear 2.43
Speed ratio of each
3-shift gear 7.87 8-shift gear 1.80
shift
4-shift gear 5.88 9-shift gear 1.34
5-shift gear 4.375 10-shift gear 1
Reverse shift speed ratio 13.91 3.18
Lubrication method Main gearbox is splash lubrication and supplementary gearbox is forced lubrication
Lubrication brand 85W/90 GL-4 or 85W/90 GL-5
Fuel charge 12L(with PTO is 12.5L)

4. Main Technological Parameters of HW 14710 Series Transmission

Model HW14710 Installation length 843
Style 10 forward shift,1 reverse shift (three-section shell)
The largest input
1400N•M Largest input rev. 2600rpm
torque
Shift position Speed ratio Shift position Speed ratio
1-shidr gear 14.28 6-shift gear 3.26
Speed ratio of each 2-shift gear 10.62 7-shift gear 2.43
shift 3-shift gear 7.87 8-shift gear 1.80
4-shift gear 5.87 9-shift gear 1.34
5-shift gear 4.375 10-shift gear 1
Lubrication method Reverse shift speed ratio 13.91 3.18
Main gearbox is splash lubrication and supplementary gearbox is
Lubrication brand
forced lubrication
Fuel charge 85W/90 GL-4 or 85W/90 GL-5
12L(with PTO is 12.5L)

5. New Developing of HW Series Transmission

Sinotruck has researched a series new transmission, including HW 20716A automatic
mechanic transmission (AMT), HW 20716X series transmission with overdrive, and will
 push out HW 18712 series transmission with 12 shifts.

Important Points of This Chapter.

Basic principle and shift figure of drive routine of HW series transmission; meaning of nameplate
and main technological parameters of the HW series transmission.

Exercises:
1. Which kinds of control structure of HW series transmission?
2. How to realize the locking, interlocking of the HW series transmission?
3. Shift figure of HW series transmission.
4. Drive routine of HW series transmission.
5. Which items of nameplate of HW series transmission?
6. Explain the numbered rule of HW series transmission.
 Chapter III Maintenance of HW Series Transmission

Requirements:
Master maintenance of HW18709、HW18710、HW14710、HW20716 transmissions, comprehend
different structure and notice items of maintenance of HW transmission, and choose suitable
repairing method to repair the transmission assembly by the on-site conditions. Master the
repairing tools of HW series transmission and can be perfect use.

Section I Dismantle and Assemble of HW Series Transmission

Assembly

I. Basic Requirements of Dismantle of HW Series Transmission

Basic Requirements as Following:
① Be familiar with the assembly requirement, shape of settled parts, the location after parts
normal installation, and prevent to use any defect parts.
② Before installation, make good inspection of parts ensure the parts surface is clean and not
district manufactured defect, especially the combined surface is not burr, bump and others,
such as the matching surface of oil seal and transitional surface when equipment and the
gear surface shall not have distinct bump and other damages.
③ Handle parts with care, not damage the parts surface, especially the important combined
surface.
④ Before installed the oil seal, lay on suitable lithium grease on the connected mouth to
protect it.
⑤ After installation, clear the copper crumbs on the parts surface to keep the surface neatness
if the parts surface is knocked on by copper hammer and others.
⑥ After installation, examine the parts to ensure it is installed in the correct position. If
debugging, please debug by requirement till meet the installation requirement.
⑦ Bolt installation: firstly put the bolt through the light hole or threaded hole, then wring the
bolt to the fixed surface 2-3 threads. Tighten the bolt on the cross, and use torque wrench to
measure the bolt torque to keep the techniques required torque.
⑧ Use suitable work position and tools to put parts neatly, not random to avoid being knocked
and accidental damage.
⑨ Keep the assemble site clean.
II. Dismantle of the Transmission Assembly.
1. Fork Axle Dismantle of Push-type Clutch
 3-1 3-2

Clean the transmission assembly, then put it on the ground with soft rubber mat (see figure
3-1). Dismantle the fork bolt of transmission, then the flat key, take off fork axle and fork to
separate bearing, low pressure hose and grease cup (see figure 3-2)
2. Fork Axle Dismantle of Pull-type Clutch.
Dismantle the two tightening screws for fastening fork and fork axle (see Figure 3-3). Take
off the elastic ring of fork axle by circlip pliers (see Figure 3-4).

3-3 3-4

Lift up fork axle, the flat key on the fork axle low end will naturally drop. Take off the flat
key (see figure 3-5), dismantle carrier bolt of fork axle and take off the fork axle carrier (see
figure 3-6).

Figure 3-5 Figure 3-6

3. Dismantle the fork axle carrier (see figure 3-7) and oil inlet of shell, oil inlet of input shaft
and oil outlet assembly (see Figure 3-8)

Figure 3-7 Figure 3-8

4. Dismantle end cover assembly of input shaft (see Figure 3-9) and end cover of
supplementary axle (see Figure 3-10. when dismantle the end cover of supplementary axle,
use plain end screwdriver to prize on the bulges of this figure).

Figure 3-9 Figure 3-10

5. Dismantle six M10 bolts connected oil pump and front housing, not dismantle two bolts
connected front and back housing of oil pump (Figure 3-11 shown by circle). Gently turn to
the input shaft to drive supplementary axle moving, make the top thread on the axle end of
left supplementary axle direct to the gap on the shell of oil pump (see Figure 3-12). Hold oil
pump and outside forcibly dismantle the oil pump assembly (if not easily dismantle, under
the condition that ensure the top thread on the end of left supplementary axle is direct to the
gap of the shell of oil pump) use M12X50 top thread to turn into the two screw holes
directed by Figure 3-11 arrow to push the oil pump out), take out of top thread from the end
of left supplementary axle (see Figure 3-13, arrow direction is the position of ball).

Figure 3-11 Figure 3-12

6. Pipe 2 in the box is clearance fit with front shell, it can be used screwdriver to hook inside
of the pipe 2 to pick it up (see Figure 3-14), and dismantle input shaft and stop ring of
supplementary axle (see Figure 3-15).
 Figure 3-13 Figure 3-14

Figure 3-15 Figure 3-16

7. Dismantle all nuts connected middle shell and front shell in the front shell (see figure 3-16),
then dismantle the nut connected middle and front shells outside of the front shell, maintain
2-3 nuts to keep the middle and front shell not split when it left (see Figure 3-17).

Figure 3-17 Figure 3-18

8. Loose the four boles on the small housing and the two hollow bolt on air pipe of range shift
cylinder, dismantle small housing assembly (see Figure 3-18， Figure 3-19).

Figure 3-19 Figure 3-20

9. Make workbench ready for input shaft impending, put the transmission on the workbench
and let the output flange of the transmission vertically and steadily dropping on the
 workbench, take care for protection the ring ridge of front shell and input shaft. Prize the
locking plate of output shaft (see Figure 3-20), and dismantle larger bolt (see figure 3-21)
by special tools of G01 or G14 (cooperate with pneumatic wrench).

Figure 3-21 Figure 3-22

10. Pull greasy blockage out by M10 bolt (see Figure 3-22), dismantle the tightening nut of
main axle in output shaft by extension bar bush (see Figure 3-23, before split main
gearbox from supplementary gearbox, it must firstly dismantle the tightening nut of
main axle, otherwise the main axle will be damaged), then fasten the larger bolt.

Figure 3-23 Figure 3-24

11. Screw off connected bolt of PTO, and then take off the back shell of PTO by M10 top
thread (see Figure 3-24). Screw off connected bolt of front shell of PTO and back shell of
transmission; take off the front shell of PTO (see Figure 3-25).

Figure 3-25 Figure 3-26

12. Screw off bolt connected back and middle shell of transmission (see Figure 3-26), prop up
the back shell of transmission by M12 top thread (see Figure 3-27), then lift up the
supplementary assembly by lifter or rope and take off the assembly.
13. Take off the input shaft of PTO by gently copper hammer striking (see figure 3-28), and put
the supplementary gearbox and PTO into the clean place.
 Figure 3-27 Figure 3-28

14. Screw five bolts of tightening lock plate in main gearbox (Figure 3-29 circle shown), take off
the lock plate, bolt, padding block, interlocking plate of main and supplementary gearbox,
lock plate pad and spring, and then take off clamp spring outside of bearing on the two
supplementary axle by using spring pliers (see Figure 3-30).

Figure 3-29 Figure 3-30

15. Bring the two idle wheel forward by pin removal G06 (Figure 3-31), then in the far away
place of supplementary axle direction to dial idle wheel to leave the position of bearing on
supplementary axle to avoid scraping between bearing of supplementary axle and idle wheel
when split front and middle shells.

Figure 3-31 Figure 3-32

16. Unscrew bolt connected filter screen end cover of transmission, take off end cover and filter
screen (see Figure 3-33) to avoid filter and gear scraping when lift up the middle shell. Lift
up the middle shell of transmission by M12 bolt, lift down the middle shell and take off the
oil pipe 1 in the box (see Figure 3-34).
 Figure 3-33 Figure 3-34

17. Use special tool G05 to dismantle the bearing on the two supplementary axles (see Figure 3-
35), take off main axle and two supplementary axles (see Figure 3-36), and turn over the
front shell, dismantle input shaft assembly by copper bar or hammer. Notice: when
dismantle HW 20176 transmission assembly, input shaft assembly, supplementary axle
assembly, main axle assembly and fork axle assembly shall be dismantled at the same
time.

Figure 3-35 Figure 3-36

III. Dismantle and Assemble the End Cover Assembly of Input shaft.
Only when oil seal of input shaft is leak, the end cover assembly of input shaft can be allowed to
dismantle. Specific techniques: firstly take off the oil guide ring of input shaft by using M6 top
thread, then take off oil seal by screwdriver or other tool, notice: not to scrap the inner surface of
end cover of input shaft. The assemblage of end cover of input shaft is as follow:
1. Lay grease on inner surface of end cover of input shaft (see Figure 3-37), put the oil seal as
Figure 3-38 shown, then assemble the oil seal to its position (see Figure 3-39).

Figure 3-37 Figure 3-38

 Figure 3-39 Figure 3-40

2. Put oil guide ring align to the oil hole on end cover of input shaft (see Figure 3-40), and
assemble the oil guide ring to its position (see Figure 3-41).

Figure 3-41 Figure 3-42

IV. Assemble the Middle Shell of Transmission

1. Put 1 idle wheel, 2 needle bearings, 2 washers as a group (see Figure 3-42) to make up two
groups to assemble the two idle wheel carriers position (see Figure 3-43). Two groups of
idle wheel, bearing and washer are same and can be changed use.

Figure 3-43 Figure 3-44

2. Ensure that the oil hole of right idle wheel is paralleling the horizontal direction of middle
shell (see Figure 3-44 arrowed direction), and assemble to its position. The oil hole of left
idle wheel direct to the support pin of lock plate (See Figure 3-45 arrowed direction), and
assemble to its position. Notice: right and left idle wheels are different, can’t be changed
to use. Inner hole of left idle wheel is larger and a through hole, one end to the inner
pipe 1 of hole connection box in middle shell, another end to hole of the fork axle of
range shift in back shell. Right idle wheel is only used to the thread blind hole for
dismantle (see Figure 3-46).
 Right idle wheel only for Left idle wheel for fork axle of
dismantle and assembly uses range shift insert.

Figure 3-45 Figure 3-46

V. Assemble the Transmission Assembly.

1. Measurement of the Main axle Adjustable Washer.
One point, measurement of main axle adjustable washer, must be noticed before assemble
the transmission assembly, otherwise the whole assembly performance will be affected.
There are 9 kinds of thickness of main axle adjustable washer, from 5.25mm to 6.45mm,
can be chosen. If following parts are changed during transmission repaired, the main axle
adjustable washer must be re-measured: main axle ball head assembly, middle shell of
transmission, planet assembly of supplementary gearbox assemble, rolling bearing 61820,
rolling bearing 63/22, spacer bush, high shift cone-hub assembly, oil guide ring assembly
and back shell of transmission.
The measurement is as following:

Figure 3-47 Figure 3-48

Put the input flange of the supplementary gearbox assembly down to stead place (the larger
bolt of the back flange must be tightened, otherwise the measurement shall be affected),
then assemble the middle shell to the supplementary gearbox (See Figure 3-47, firstly not
assemble the paper washer of supplementary gearbox, but put it on the special measuring
plate G １ 5). Fit a pre-chosen main axle adjustable washer on the screw of main axle
assembly (to avoid the adjustable washer and hex key dropping down, lay grease on the
connection to keep then on the main axle), and then put the spline key of main axle
assembly to the spline hole of sun wheel in the supplementary gearbox. Put the measure
plate on the middle shell in level way (see Figure 3-48, for convenient working, the arrowed
place in the Figure is putting the paper washer of supplementary gearbox under the depth
ruler after the paper washer was cut a section), and record the measure distance from the
paper washer of supplementary gearbox to the three-shift gear of main axle as A, the
thickness of measure plate as B (date chiseled on its surface), and the thickness of pre-
chosen main axle adjustable washer fitted on the main axle as C.
The chosen adjustable washer, (for HW18709 、 HW18710 and HW14710 series
transmissions), needs to ensure that the distance from the front end of the middle shell to the
gear end of three-shift gear of main axle is 69.22±0.2mm, and (for HW 20716 series
 transmission) the distance from the front end of the middle shell to the gear end of drive
gear (high) of main axle is 95.57±0.10 mm. The thickness of final-chosen main axle
adjustable washer shall be ensured the above-mentioned data.
For example: HW 18709 series transmission assembly, the actual distance from paper
washer of supplementary gearbox to three-shift gear of main axle is 94.18, the thickness of
measure plate is 24.58, the thickness of pre-chosen main axle adjustable washer is 5.85,
therefore, the required thickness of main axle adjustable washer is: 94.18-24.58+5.85-
69.22=6.23, so the final chosen thickness is 6.30mm, which is much closed to the thickness
6.23mm of main axle adjustable washer.
After measurement finished, assemble of the transmission assembly is as following:
2. Assemble HW18709、HW18710 and HW14710 Series Transmission Assembly
① Support the front shell by soft material; take care of leaving position of input shaft in the
middle of the shell and stable. Use copper bar or hammer to gently strike the input shaft
assembly (see Figure 3-49), let one short section of bearing into the bearing hole of forward
shell. In addition, screw one M16 hollow bolt on the other side of arrowed place on the
figure.
② Mark a line on the root of the gear of input shaft, turn the input shaft and make the marked
line and center of the two supplementary axle holes on the same line (see Figure 3-50).
Alone the flat key of supplementary axle of its two assemblies to draw a line (see Figure 3-
51, gap arrowed and directed by the circle), and then hit the bearing of supplementary axle
to its position, take care of the stop groove of bearing is in the outside to put the stop ring
from the inner of front shell.

Figure 3-49 Figure 3-50

Figure 3-51 Figure 3-52

③ Put the slip bush on the front end of the main axle (notice: spline gap of main axle slip bush
direct to the hex key), then put them into the bush guide hole of input shaft together (see
Figure 3-52), push the two supplementary axle assemblies to the holes of supplementary
axle. Left and right supplementary assembly shall not put wrong position (as Figure 3-53
arrow shown, the end of right supplementary axle has a spline groove for combine with the
spline axle of PTO), the marked line on the supplementary axle shall be aligned to the first
axle line (see Figure 3-53). Notice: the tooth of gear shall not be wrong; otherwise all
the gear can’t be correctly engaged.
 Figure 3-53 Figure 3-54

④ Put the fork of fork axle assembly insert the groove of main axle slip bush in turn, fork axle
insert the hole of front axle, and take care of the correspond position of fork axle assembly
shall not be wrong (Figure 3-54). And then, by copper bar assemble the supplementary axle
assembly, main axle assembly, fork axle assembly, input shaft assembly to its position in
turn. After that, put the pipe 1 in the box insert the oil pipe of front shell (Figure 3-55).

Figure 3-55 Figure 3-56

⑤ Lay Loctite 242 tightening glue on the inside of screw thread hole connected the middle
shell and front shell, put 25 double heads studs and tighten by wind trigger, hit into the
locating spins. Lift up the middle shell assembly equipped with front shell paper washer;
roughly align with the front shell (see Figure 3-56). Put a cross screwdriver into the hole of
left idle wheel axle, in order to guide the pipe 1 of main gearbox into the hole of left idle
wheel axle (see Figure 3-57). Dial the idle wheel and reverse gear of main axle, put fork
axle insert the hole of fork axle in the middle shell in turn, meanwhile, put the locating pin
and double heads stud of middle shell into the correspond hole of front shell. After that, hit
the place as shown in Figure 3-57 by copper bar to assemble the middle shell to its position.
⑥ Put the two supplementary axle bearing into its axle positions (see Figure 3-58), take care of
the larger rounding chamfer of bearing shift ring is adown. Then put the two supplementary
axle clamp spring by use circlip Pliers (see figure 3-59), equip with the measured main axle
adjustable washer into the main axle.

Figure 3-57 Figure 3-58

 Figure 3-59 Figure 3-60

⑦ Assemble lock washer plate, spring, interlocking plate of main and supplementary gearbox,
pressure plate block, locking pressure plate (large), locking pressure plate (small) in turn
(see Figures 3-60、2-61、2-62、2-63). Notice: anything shall not drop into the middle shell.
Notice: interlocking plate, locking washer plate, locking pressure plate (large) of
HW18710 、 HW14710 series transmission are different from those of
HW18709、HW20716 series.

Figure 3-61 Figure 3-62

⑧ Lay Loctite 271 screw thread glue on the 5 heads of bolt of interlocking device of main and
supplementary gearbox, then tighten them, the torque is 41-51Nm (see Figure 3-64). Dial
the interlocking palate, its return agility. If its return is not agility, the clearance between the
interlocking plate and washer plate shall be adjusted (see Figure 3-65). Lay grease on the
end of middle shell; post the paper washer of supplementary gearbox onto the middle shell,
and pay attention to align the locating pin, screw thread hole and paper washer hole.

Figure 3-63 Figure 3-64

 Figure 3-65 Figure 3-66

⑨ Pull the interlocking plate to the position away from the idle wheel hole by use iron wire to
stick in the middle of interlocking plate and locking pressure plate, so that the fork axle of
range shift can smoothly insert (see Figure 3-66). Air the cylinder of range shift to make it
in the high shift position (if not air the cylinder, firstly dismantle the cylinder of range shift,
and then push piston to close the back shell of the transmission). Lift up the supplementary
gearbox assembly; let the fork axle of range shift insert the hole of left idle wheel; bearing
of supplementary gearbox align the ring ridge of bearing in middle shell; turn output flange
to let the spline groove in sun wheel of supplementary gearbox align with the spline of main
axle. Meanwhile, align the locating pin on the shell of transmission (see Figure 3-67).

Figure 3-67 Figure 3-68

⑩ Assemble the supplementary gearbox to its position, and lay loctite 242 screw thread glue
on the thread heads in turn, and then tighten the thread into the connection hole of main and
supplementary gearboxes, the torque is 41-51Nm. There are 3 kinds of connection bolt, pay
attention to its position and lifting plate position (see Figure 3-69). Unscrew the large back
bolt; lay locitite 271 screw thread glue on thread of main axle tightening nut (see Figure 3-
69); tighten into the screw thread of main axle ball head, its torque is 73-89Nm; push the
groove on screw thread bolt of main axle ball head to open after tightening to lock the screw
thread.

Figure 3-69 Figure 3-70

Assemble the oil blockage assembly and elastic column pin on the end of output shaft (see
Figure 3-70); lay enough plane seal glue on the spline of connection of flange and output
shaft (see Figure 3-71), and then put into the pressure plate and tighten the large bolt.
 Figure 3-71 Figure 3-72

Tighten the large bolt by special tool G01 or G14 with wind trigger (or lengthening splice
bar), its torque is 1200-1300Nm (see Figure 3-72), put into the locking plate and clinch (see
Figure 3-73).

Figure 3-73 Figure 3-74

Assemble of HW50 PTO

Put the needle bearing into the back end hole of input shaft of PTO, align with the inner
hole of spline on the right supplementary axle, and then assemble the input shaft of PTO to
the PTO hole of back shell (see Figure 3-74). Put the paper washer of end cover on output
shaft of PTO, O ring, and then put the front shell of PTO to its back shell, and its bolt
tightening torque is 73-89Nm (see Figure 3-75).

Figure 3-75 Figure 3-76

Lay grease on the combined face of front shell of PTO, and post PTO paper washer on the
front shell of PTO (see Figure 3-76), and then connect the back shell of PTO with the front
shell, the bolt tightening torque is 41-51Nm (see Figure 3-77).
 Figure 3-77 Figure 3-78

Assemble method of HW70 is similar with the HW PTO; lay seal glue in the middle of front
and back shells of PTO, the most important is the glue shall be even to ensure the seal
interface not to be leak.
Other Parts Assemble.
Put the filter screen assembly, o ring, end cover of filter screen into the middle shell by bole,
the bolt tightening torque is 21-25Nm (see Figure 3-78), and then tighten the nut connected
middle and front shells in turn. Pay attention to install lifting plate (see Figure 3-79 arrowed
place).

Figure 3-79 Figure 3-80

Lay the transmission assembly on the plane ground by lifter, and pay attention to safety and
stability. Install the input shaft and stop ring of two supplementary axles (see Figure 3-80)
and its clamp spring (see Figure 3-81).

Figure 3-81 Figure 3-82

Measure the thickness of input shaft adjustable washer (there are 3 thickness of washers can
be chosen: 0.15、0.20、0.25). gently hit the end of input shaft by copper hammer, let the stop
ring of input shaft to be close to the end of front shell, and measure the distance from the
end of bearing of input shaft to front shell by depth rule, recorded as A (see Figure 3-82);
put the paper washer on the end cover of input shaft, and measure the distance from paper
washer to ring ridge of bearing, recorded as B (see Figure 3-83), and then choose the
adjustable washer which thickness is between B-A-0.1 and B-A.
 Figure 3-83 Figure 3-84

Lay suitable grease on the middle of end cover of input shaft and paper washer, and put it
with chosen adjustable washer into the front shell by order; the thread of screw must be laid
Locitite 242 screw thread tightening glue on, its tightening torque is 41-51Nm (see Figure
3-84); put the end cover of supplementary axle, paper washer into the end of right
supplementary axle, and must lay Locitite 242 tightening glue on the bolt thread, its
tightening torque is 41-51Nm (see Figure 3-85).

Figure 3-85 Figure 3-86

Lay grease on the relevant combined interface of front shell, and after paper washer on end
cover of supplementary axle and paper washer of oil inlet align with the hole each other,
post them on the front shell. Install the drive top thread of oil pump into the hole of left
supplementary axle (see Figure 3-87 arrowed shown), top thread align with the gap of oil
pump (see Figure 3-87), and install the oil pump assembly (see Figure 3-88). Notice: there
are 3 kinds of oil pump tightening bolt with different length (including Figure 3-88, the bolt
5 is Q150B1040, bolt 6 is Q150B1090, and other bolt is Q150B1070), its thread must lay
Locitite 242 tightening glue and its torque is 41-51Nm, among them there are 2 bolts use
flat washer, and the screw shall be laid enough plane seal glue on the bolt (see Figure 3-88,
bolt 1 and bolt 4), others are spring washer.

Figure 3-87 Figure 3-88

 Figure 3-89 Figure 3-90

Insert pipe 2 of gearbox (see Figure 3-89), connect all oil pipe assemblies, and the
tightening torque of hollow bolt is 50±10% N•M, the largest torque is not more than 60Nm
(see Figure 3-90).
Connect fork axle with bush assembly to the front shell (see Figure 3-91); put the fork axle
of clutch through the bush hole of front shell, and install flat key (see Figure 3-92), and then
pass split fork, fork axle carrier, and connect the split bearing at the same time and connect
left and right connection spring. After the fork axle of clutch turning agility, then fasten the
fork axle carrier; if turning not agility; gently strike the fork axle carrier. Notice: the screw
thread, connected the bolt of carrier of fork axle, must be laid Locitite 242 tightening glue
(see Figure 3-91), its tightening torque is 41-51Nm, and tightening bolt torque of split fork
axle of clutch is 21-25Nm, and the inner hole of complex bush must be laid on enough
grease.

Figure 3-91 Figure 3-92

Connect the low pressure oil pipe with the split bearing of clutch and front shell (see Figure
3-93), and install grease mouth (cup) on the front shell; fill enough grease into the split
bearing of clutch by the grease mouth (cup) (see Figure 3-94).

Figure 3-93 Figure 3-94

Install the paper washer and assembly of small housing onto the transmission assembly
which required shift choice agility. The connected bolt head shall lay Locitite 242 tightening
glue, and its torque is 41-51Nm (see Figure 3-95). Connect air pipe with the double H valve
and range shift cylinder, and pay attention to the air pipe connection not wrong (see Figure
 3-96 arrowed place that is two closed end connections and two far end connections).
Hollow bolt torque is 42±10%N•M. Install the reverse switcher, neutral switch, pressure
switch of range shift on the small housing, and all the pressure switches torque is less than
35Nm (see Figure 3-96, the arrow directed places of 2, 3, 4, and 5 is reverse switcher,
neutral position switcher, range shift switcher and PTO switcher).

Figure 3-95 Figure 3-96

Install oil inlet pipe of supplementary gearbox and PTO oil Pipe, M16 hollow bolt torque is
50±10%N•M(see Figure 3-97). Examine the entire oil pipe to ensure there are not leak. Install
soft axle carrier (see Figure 3-98).

Figure 3-97 Figure 3-98

Air Piping Installation of Small Housing of HW18710 and HW14710

Figure 3-99 Figure 3-100

As Figures of 3-99 、 2-100 shown that installation of the air piping of small housing of
HW18710 is two close end connection and two far end connection.
After the transmission assembly installation, carefully examine the transmission and test the
signal condition of all the pressure switchers to ensure that there are not any wrongs, and
then equip it with the vehicle.
3 Assemble of HW20716 Transmission Assembly (Others as same as HW18709).
① Support the front shell by soft material and pay attention to leave the position of input shaft
and ensure the position is safety and reliability. Put station on the hole of input shaft of front
shell (see Figure 3-101); put the input shaft assembly (see Figure 3-102) into the hole of
front shell, and install the synchronizing slip bush and make the center of sector gap of
inner ring align with the small open groove of input shaft (see Figure 3-103); put the spring
of ejector pad into the outside spring, and then install the two pieces to the synchronizing
ejector pad and locating (totally three groups, see Figure 3-104), meanwhile, install the
three pieces into the small open groove of input shaft. In addition, on the other side of arrow
directed place, screw a M16 hollow bolt (see Figure 3-101).

Figure 3-101 Figure 3-102

Figure 3-103 Figure 3-104

② Put the synchronizing ring on the input shaft; let the large bulges station of synchronizing
ring align with the large open groove of input shaft(see Figure 3-105); install the main axle
assembly into the guide bush hole in back end of input shaft (see Figure 3-107).
③ Put the fork swing block into the hole of insert and split shift fork (see Figure 3-106), and
let the fork swing block inset the synchronizing slip bush, and install insert and split shift
fork axle into the correspond hole of front shell and locating. Assemble three- and four-shift
gear, one- and two-shift gear assembly in turn, and let the fork insert into the groove of
main axle slip bush (see Figure 3-108).

Figure 3-105 Figure 3-106

 Figure 3-107 Figure 3-108

④ Put the reverse shift slip bush onto the top end of main axle, and pay attention to the hex
key position. The thicker side of reverse shift slip bush is adown; install the reverse shift
fork axle to its position, and let fork insert into the groove of slip bush, and fork axle insert
into the correspond hole of front shell (see Figure 3-109).

Figure 3-109

⑤ Draw a symmetry line on the top of the gear of drive gear (low) of input shaft (see Figure 3-
110). Draw a line along the direction of long flat key of supplementary axle in the two
supplementary axle assemblies (see Figure 3-111, gap directed by left arrow and circle), and
then install the supplementary axle bearing, and pay attention to the stop groove on the
bearing is toward outside, for being convenient to install stop ring in the front shell.

Figure 3-110 Figure 3-111 Figure 3-112

⑥ Put the two supplementary axles onto the bearing holes of front axle, let the gear top which
marked by line on the (low) drive gear of supplementary axle engage to the gear groove
marked by line on two teeth of gear on input shaft, and then pull out the station (see Figure
3-112), and pay attention to the position of left and right supplementary axles shall not be
wrong (there is spline groove on the end of right supplementary axle assembly to cooperate
with the PTO spline axle, such as Figure 3-113, the arrow directed place is right
supplementary axle assembly). Install input assembly, main axle assembly and two
supplementary axles to its positions.

Figure 3-113 Figure 3-114 Figure 3-115

⑦ After the axle assembly installation, dial the main axle slip bush to the neutral position, and
dial the insert and split shift to low or high shift position, and then turn the two
supplementary axle assemblies to turning agility, and ensure tooth align correctness (see
Figure 3-114). Install pipe 1 of gearbox to its position (see Figure 3-115).
⑧ Lay Locitite 242 tightening glue on the thread hole on the middle shell connected with front
shell, install 25 double heads stubs and fasten them by wind trigger (notice: the double
heads shall not be installed in the thread hole connected with the oil pump), use copper
hammer hit the two locating spins into its positions. Lifting up the middle shell assembly
installed paper washer of front shell, align with the front shell (see Figure 3-116). Insert a
screwdriver from the hole of left idle wheel axle, so that the pipe 1 of main gearbox can be
guided into the hole of left idle wheel axle when the middle housing dropping down (see
Figure 3-117). Dial idle wheel and reverse gear of main axle, insert the fork axle to the hole
of fork axle on the middle shell, meanwhile, insert the locating pins and double heads stub
on the middle shell into the hole of correspond hole of front shell, and then assemble the
middle shell to its position.

Figure 3-116 Figure 3-117

Assemble Insert and Split Shift and Locking Device
① Install insert and split shift piston, and there are o rings inside and outside of piston (see
Figure 3-118). Before install the fastening nut, the thread shall be laid on Locitite 271
tightening glue (see Figure 3-119).

Figure 3-118 Figure 3-119

② Lay suitable grease on the inner wall of cylinder of insert and split shift and o rings (such as
Figure 3-120), put on paper washer and install cylinder of plug-in and split shift, and align
the air inlet hole of cylinder with the combined air hole of back shell (see Figure 3-120
arrow directed place), and then lay Locitite 242 tightening glue on the bolt thread, its
tightening torque is 41-51 Nm (see Figure 3-121).

Figure 3-120 Figure 3-121

③ Install locking top thread, locking spring and inner hex screw plug (see Figures 3-122, 3-
123).
 Figure 3-122 Figure 3-123

Others Assemble are as same as HW 18709 Series.

4. Assemble the Parts of Pull-type Clutch
① After lay suitable Locitite 242 tightening glue on the connected bolt, install the fork axle on
the front shell (such as Figure 3-124 shown).

Figure 3-124 Figure 3-125

② Let the fork axle pass the fork axle hole, split fork, fork axle carrier in turn and install flat
key on the top key groove and locating. Let the fork axle install to the bottom and another
end equipped with flat key.
③ Install the low end elastic ring of fork axle by use circlip pliers, and then fasten the two
bolts connected fork and fork axle (see Figure 3-127).

Figure 3-126 Figure 3-127

④ Install assist cylinder carrier, and finish the assembly of control device of pull-type clutch as
Figure 3-128 shown.
 Figure 3-127

Section II Dismantle and Assemble of HW Series Transmission Axle

Assembly.

I. Dismantle of Axle Assembly (Supplementary Axle Needs not Dismantle,

Change the Supplementary Axle when it Repairing)

Figure 3-129 Figure 3-130

① Lift up the middle shell, and take off the main axle and fork axle. Punch the pins on fork
and fork block in turn by use punch nail (see Figure 3-129), and punch the pins out of its
position, and then finish the fork axle dismantle.
② Let the main axle in vertical condition, take off hex key, and turn the large barrier chip of
main axle. When the key groove aligns with the spline of main axle, the large barrier chip,
and reverse shift gear can be taken off. By this method, all the parts of the main axle can be
dismantled (see Figure 3-130).
③ Dismantle elastic barrier ring, input shaft bearing, spacer bush, gear elastic barrier ring, one
axle gear (reference the dismantle figure of input shaft in parts list). If only changing the
bearing of input shaft, the outside parts, such as separation bearing, oil pipe, end cover of
input shaft, stop ring, elastic barrier ring and others, only need to be dismantled. Use special
G08 to clamp the Snap ring groove of input shaft to dismantle the bearing of input shaft (see
Figure 3-131).
 Figure 3-131 Figure 3-132

II. Axle Assembly Installation

1. Input shaft Assembly of HW18709、HW18710 and HW14710 Series Transmission
① Put elastic barrier ring for hole into one axle gear by circlip pliers (see Figure 3-132); install
input shaft bush into the inner hole of back end of input shaft and locating (see Figure 3-
133).
② Put clamp spring of one axle gear belt, spacer bush, rolling bearing (notice: outside snap
ring groove of rolling bearing directs to the front of transmission), onto the input shaft, and
use special tool G10 to install rolling bearing to its position (see Figure 3-134); put elastic
barrier ring for axle use into the snap ring groove by circlip pliers, and pay attention that
there are more groups of barrier ring for axle use, and after elastic barrier ring for axle is
installed, it shall be ensured the distance between elastic barrier ring for axle and bearing is
less than 0.10mm (see Figure 3-135).

Figure 3-133 Figure 3-134

Figure 3-135 Figure 3-136

2. Input shaft Assembly of HW20716 Series Transmission.

① Install insert and split synchronizer cone hub onto the drive gear (low) assembly (see Figure
3-136); let the large bulges station of synchronizing ring is adown and insert to the large
open gar of the input shaft, and let the synchronizer cone hub is adown, then install the
 drive gear (low) assembly and rolling bearing (notice: the outside snap ring groove of
rolling bearing shall direct the front of transmission), see Figure 3-137.

Figure 3-137 Figure 3-138

② Use special tool G10 to install rolling bearing to its position (see Figure 3-138); use circlip
pliers to put elastic barrier ring into the clamp spring groove of input shaft, and pay
attention that there are more groups of barrier ring for axle use, and after elastic barrier ring
for axle is installed, it shall be ensured the distance between elastic barrier ring for axle and
bearing is less than 0.10mm (see Figure 3-139).

Figure 3-139 Figure 3-140

3. Main Axle Assembly installation of HW18709 、 HW18710 and HW14710 Series

Transmission
① Put 2 elastic column pins to the bottom of pin hole of main axle (see Figure 3-140); put the
elastic barrier ring for hole use into the clamp spring grooves of three-shift gear, two-shift
gear, one-shift gear, creep-shift gear and reverse shift gear (see Figure 3-141) in turn by
using circlip pliers.

Figure 3-141 Figure 3-142

② Let the main axle vertically stand, firstly put the large barrier chip onto the main axle and
turning the half gear (use wood plug to insert to prevent it running more); the axle locating
between gears is as Figure 3-142 shown: spline adjustable chip can realize its locating by
 turning half gear and passing hex key (can use punch to adjust the whole chip to drive the
half gear running); reference the locations of all parts in the parts explosive list Figure to
finish the main axle assembly installation. Adjust the axle clearance between gears, and the
axle clearance of three-shift gear and two-shift gear, one-shift gear and creep shift gear is
o.15-0.35mm, and reverse gear to large barrier chip of main axle is 0.30-0.50mm, its
measuring method is as Figure 3-143 shown, the measuring tool is clearance gauge, and pay
attention that hex key shall have installed 2 pieces.

Figure 3-143 Figure 3-144

4. Installation of Fork Axle

All kinds parts correspond positions of reverse shift fork axle assembly, one/two shift fork
axle assembly, three/four fork axle assembly, insert and split fork axle assembly can take
reference as explosive Figure of parts list shown. When installing pins of fork axle or fork
block, firstly put the pins in the symmetry position, then punch the two ends of pins off, and
pay attention to it shall be firm and stead to ensure that will not loose during using period
(see Figure 3-144).
5. Main Axle Assembly installation of HW20716 Series Transmission
① Put 2 elastic column pins to the bottom of pin hole of main axle (see Figure 3-145); put the
elastic barrier ring for hole use into the clamp spring grooves of drive gear (high) three-shift
gear, two-shift gear, one-shift gear, and reverse shift gear (see Figure 3-146) in turn by using
circlip pliers.

Figure 3-145 Figure 3-146

② Let the main axle vertically stand, firstly put the large barrier chip onto the main axle and
turning the half gear (use wood plug to insert to prevent it running more); then install the
drive gear (high) and spline barrier chip; choose suitable spline adjustable washer to ensure
the clearance from drive gear (high) to large barrier chip is 0.15-0.35mm. After that,
dismantle the drive gear (high), and put the insert and split cone-hub into the drive gear
(high) as Figure 3-147 shown, then put the chosen spline barrier chip and adjustable chip
together onto the main axle. spline adjustable chip can realize its locating by turning half
gear and passing hex key (can use punch to adjust the whole chip to drive the half gear
running); reference the locations of all parts in the parts explosive list Figure to finish the
main axle assembly installation. Choose suitable thickness of spline adjustable chip to
ensure the axle clearance of three-shift gear and two-shift gear is o.15-0.35mm, one-shift
 gear and reverse gear is 0.30-0.50mm, its measuring method is as Figure 3-148 shown, the
measuring tool is clearance gauge, and pay attention that hex key (316 long) shall have
installed 2 pieces.

Figure 3-147 Figure 3-148

Section III Dismantle and Assemble the Supplementary Gearbox

Assembly of HW Series Transmission

I. Dismantle the Supplementary Gearbox Assembly

① Let the output flange upward, dismantle the large bolt, pressure plate (see Figure 3-149) and
use special tool G16 to dismantle the output flange (see Figure 3-150).

Figure 3-149 Figure 3-150

② Dismantle cylinder of range shift, piston (see Figure 3-151), end cover of output shaft (see
Figure 3-152, it has 8 fastening bolts).
 Figure 3-151 Figure 3-152

③ Dismantle 2 support pins of fork axle (see Figure 3-153, the two arrows direct place), and
dismantle the bolt connected the torque drive chip with back shell (see Figure 3-154).

Figure 3-153 Figure 3-154

④ After dismantling the back shell of transmission, use special tool G03 to dismantle bearing
of planet carrier (see Figure 3-155). Turn over the planet device and use special tool G17 to
dismantle worm gear of odometer, rolling bearing (see Figure 3-156).

Figure 3-155 Figure 3-156

⑤ Keep suitable clearance between high shift cone-hub and synchronizing gear seat, and use
special tool G04 to dismantle high shift cone-hub (see Figure 3-157) and take off the
synchronizing ring; lift up synchronizing slip bush by two hands, and pay attention to not
lose and scattered ejector pad, inner and outside springs (see Figure 3-158).
 Figure 3-157 Figure 3-158

⑥ Use circlip pliers to take off the elastic barrier ring clamped in the carrier of gear ring (see
Figure 3-159); use special tool G04 as Figure 3-157 shown to clamp the under part of
synchronizing ring (see Figure 3-160) and dismantle the synchronizing gear seat,
synchronizing ring and low shift cone-hub assembly.

Figure 3-159 Figure 3-160

⑦ Dismantle snap ring, bearing in the carrier of gear ring, and take off steel wire barrier ring,
inner gear ring (see Figure 3-161); the rest parts of planet carrier, input shaft and inner sun
wheel, planet wheel, washer and others need not to dismantle as a entire, called planet
device assembly (see Figure 3-162), and change it by a part when repairing.

Figure 3-161 Figure 3-162

II. Supplementary Assembly Installation of HW 18709 and HW20716 Series

Transmission
① Put o ring into the middle of oil inlet hole in the back shell of transmission and ring groove
of fork axle hole of range shift, and lay grease on the o ring (see Figure 3-163, 3-164). For
 supplementary gearbox assembly of HW20716 transmission, it also needs to put o ring
into the hole of fork axle of insert and split shift.

Figure 3-163 Figure 3-164

② Choose the adjustable washer in the end cover of output shaft: put paper washer on the end
cover of output shaft, and measure the depth from paper washer to ring ridge of end cover
of output shaft (see Figure 3-165) A, to back shell thickness B (see Figure 3-166), and
distance C from rolling bearing to oil guide ring (see Figure 3-167), then the thickness of
adjustable washer is between A+B-C-0.1 and A+B-C. And install joint of odometer to its
position (see Figure 3-168).

Figure 3-165 Figure 3-166

Figure 3-167 Figure 3-168

③ Use connected bolt to join the transmission back shell, assembly of oil guide ring, bearing,
chosen adjustable washer, back end cover of output shaft together, and their torque is 41-
51Nm; pay attention to lay enough plane seal glue on the longest connected bolt to prevent
oil leakage on the bolt point (see Figure 3-169).
 Figure 3-169 Figure 3-170

④ Put bearing in the carrier of gear ring, and clamp elastic barrier ring for hole use; use punch
to punch the elastic barrier ring to its position (see Figure 3-170); install the carrier of gear
ring into the inner gear ring, and clamp the steel wire barrier ring; (see Figure 3-171), use
punch to punch the steel wire barrier ring to its position (see Figure 3-172).

Figure 3-171 Figure 3-172

⑨ Put gear ring module in the planet carrier assembly and align the teeth, then put on the
spacer bush (its gap upward); use tube processor G09 to install the gear ring module to its
position, turn the inner gear ring to ensure it engages with planet wheel and turning agility
(see Figure 3-173); install low shift cone-hub assembly, synchronizing ring, synchronizing
gear seat (notice the settle direction of gear seat) it turn, and use G09 to install them to their
positions (see Figure 3-174).

Figure 3-173 Figure 3-174

⑩ Use circlip pliers to install axle elastic barrier ring of synchronizing gear seat (see Figure 3-
175); when installing synchronizing slip bush, pay attention to the groove of synchronizing
slip bush is opposite to the groove of synchronizing gear seat (see Figure 3-176).
 Figure 3-175 Figure 3-176

Firstly install the outside and inner springs and ejector pad of 9 ejector pads to its positions,
and pay attention to the synchronizing ejector pad direction, then install the synchronizing
ring (see Figure 3-177); draw a line on the gear groove of oil hole in output shaft by remark
pen, let short of tooth place of the inner gear of high shift cone hub directs to the remark
line, and install the high shift cone-hub to its position (see Figure 3-178).

Figure 3-177 Figure 3-178

Install fork of range shift (notice gap direction), fork swing block, range shift fork axle to
the synchronizing slip bush, and pay attention to the range shift fork axle position (see
Figure 3-179); if the torque drive bush is left the top of the low shift cone-hub assembly, use
punch to push it the same level as torque drive plate (see Figure 3-179 arrow directed
place); put the back shell assembly into the planet carrier assembly, and pay attention to the
fork axle of range shift aligns to the fork axle of range shift in back shell, and then install
the back shell to its position (see Figure 3-180).

Figure 3-179 Figure 3-180

Use special tool G09 to install bearing of output shaft, worm ring of odometer to its
positions (see Figure 3-181); use special tool G11 to install oil seal of output shaft to its
position, and notice the oil seal direction and lay grease on the mouth of oil seal (see Figure
3-182).
 Figure 3-181 Figure 3-182

Lay Locitite 242 glue on the screw thread of support pin of fork axle, then screw it to the
back shell and pass through the pin hole of fork of range shift, its torque is 195-215Nm (see
Figure 3-183); put the flange in its position, but before installing its position, the drive axle
shall connect with the bolt (see figure 3-184, 3-183).

Figure 3-183 Figure 3-184

Figure 3-185 Figure 3-186

Install pressure pate, large bolt in turn, and screw large bolt, its torque is less than 300Nm
(see Figure 3-186); put the piston assembly of range shift (including piston of range shift,
interior and exterior o rings) on the fork axle of range shift; lay Locitite 271 glue on the
inner thread of locking nut and its torque is 119 -145Nm (see Figure 3-185).

Put the paper washer of range shift cylinder, range shift cylinder (with seal ring and pressure
switch) on the piston of range shift in turn, notice the groove of back shell aligns to the air
inlet of range shift cylinder; before installation, lay suitable grease on the inner wall of
cylinder and o ring of piston and ensure there are not any dirty on each parts; use
connection bolt which thread laid Locitite 242 glue to fasten cylinder of range shift to the
back shell, its torque is 41-51Nm (see Figure 3-187).
 Figure 3-187 Figure 3-188

Turn supplementary gearbox assembly over, and align the holes of torque drive plate and
back shell, hit the torque bush to the level as torque drive plate (see Figure 3-188); lay
Locitite 271 glue on the connection bolt and screw it into the thread hole of torque drive
bush, its torque is 73-89Nm.
Put the front bearing of planet carrier to its bottom (see Figure 3-189); rivet 3 points on the
touching edge of planet carrier and bearing to prevent the bearing escaping outward (see
Figure 3-190).

Figure 3-189 Figure 3-190

After supplementary assembly installation, test the two air holes of range shift cylinder to
ensure shift change of range shift in supplementary gearbox is agility.
III. Supplementary Gearbox Assembly Installation of HW18710 Transmission
Compared with HW18709 transmission, the difference of supplementary gearbox of
HW18710 exists at:
① When installing torque drive bush, by longer torque drive bush joint the locking block of
range shift to back shell and torque drive plate together; lay Locitite 271 glue on the
connection bolt and screw it to the thread hole of torque drive bush, its torque is 73-89Nm
(see Figure 3-191); fork axle of range shift is with two grooves (see Figure 3-192).

Figure 3-191 Figure 3-192

② Put top thread, lock spring of range shift, hex screw plug fastening glue on its thread into the
hole of snap ring pad of range shift, and tighten it by inner hex wrench (such as Figures 3-193, 3-
194 shown).

Figure 3-193 Figure 3-194

Section IV Dismantle the Small Housing Assembly of HW18709 and

HW20716 Series Transmission

I. Dismantle the Small Housing.

① Loose the locking nut on swing arm of shift, and dismantle shift swing arm and anti-dust
cover (see Figure 3-195); and dismantle all the pressure switchers, sensor end pins, double
H valves and air plugs (see Figure 3-196).

Figure 3-195 Figure 3-196

② Unscrew the connection bolt of end cover of small housing (swing arm side) and small
housing shell, take off the end cover of small housing (swing arm side), and no permit to
dismantle the oil seal of small housing end cover (swing arm side) and complex shim, and if
damaged, it needs destroyed dismantle and not damage the interface of the small housing
end cover (swing arm side) (see Figure 3-197); use punch to dismantle the connected elastic
column pin of sensor drive ring, take off sensor drive ring, sector locking block and drive
pin (see Figure 3-198).
 Figure 3-197 Figure 3-198

③ Unscrew inner hex screw plug of two sides, take off seal ring, locking pin of range shift,
spring of range shift (see Figure 3-199), and dismantle bolt connected small housing end
cover (side of range shift) and small housing shell, take off small housing end cover (side of
range shift), centering spring (side of low shift), spacer ring, centering seat ring (see Figure
3-200).

Figure 3-199 Figure 3-200

④ Take off the needle of locking pin axle, and then the locking pin axle, locking spring (see
Figure 3-201); dismantle bowl-style shim, punch off the column pin connected shift head
and shift axle, and then take off shift axle assembly, shift head and interlocking fork (see
Figure 3-202).

Figure 3-201 Figure 3-202

⑤ Dismantle fastening bolt connected spacer bush and small housing shell, take off spacer
bush, centering seat ring, centering spring (high shift side) (see Figure 3-203); in generally,
the complex bush and bush on the small housing shell need not dismantle; if damaged, use
punch to punch it off, but not damage the small housing shell; after punch off the elastic
column pin connected locating spring of high and low shift and shift axle, the high and low
 shift axle ring can be dismantled.

Figure 3-203 Figure 3-204

II. Installation of Small Housing Assembly

① Install the complex bush in the small housing end cover (swing arm side) (see Figure 3-
204), use special tool G11, G12 to install oil seal inside and outside of end cover (see Figure
3-205, 3-206, 3-207), and lay enough grease on the inner hole of complex bush, mouth of
oil seal.

Figure 3-205 Figure 3-206

Figure 3-207 Figure 3-208

② Put complex bush into the small housing shell and to its position (see Figure 3-208), and lay
suitable grease on the inner hole of complex bush; lay Locitite 680 bond on the bush and
ensure to cover all the column face, and spray Locitite 7649 bond, and then install it into the
small housing shell to its position (see Figure 3-209).
 Figure 3-209 Figure 3-210

③ Install centering spring (high shift side), centering seat ring (see Figure 3-210), spacer bush
(notice direction, see Figure 3-211) in the small housing shell; lay Locitite 242 fastening
glue on the thread of tightening bolt, screw the tightening bolt on the small housing shell
(see Figure 3-211 arrow directed place) to realize the spacer bush locating.

Figure 3-211 Figure 3-212

④ Put interlocking fork and shift head into the small housing cover, pass shift axle assembly to
inner holes of interlocking fork and shift head and install shift column pin to its position
(see Figure 3-212, 3-213); use punch to punch off the two end of column pin of shift head to
ensure the pin connection is firm and reliable (see Figure 3-214).

Figure 3-213 Figure 3-214

 Figure 3-215 Figure 3-216

⑤ Put locking spring into the locking spring hole of small housing shell, pass locking pin axle
(cone end outward) through pin hole and spring barrier chip and locking spring, then put on
needle (notice barrier chip direction) and keep the rolling needle clamp on the groove of
barrier chip (see Figure 3-215); install drive pin to its position, put on sector locking block
and let locking pin axle clamp to the groove of sector locking block; install sensor drive ring
(notice direction: HW18709 is as Figure 3-216 circle shown, HW20716 direction need
turning 180°around axle center of shift axle opposite to the Figure given direction), and
then locate it by use elastic column pin.

⑥ Lay full of grease on the open of oil seal on small housing end cover (swing arm side),
fasten small housing end cover (swing arm side) on the small housing shell by connection
bolt; there is paper washer between small housing end cover (swing arm side) and small
housing shell, the connection bolt torque is 21-25Nm (see Figure 3-217); install anti-dust
cover, shift swing arm to its positions, and screw locking nut. The central line of short arm
of shift swing arm (see Figure 3-218) is vertical to the surface of small housing.

Figure 3-217 Figure 3-218

⑦ Install locking pin, locking spring of range shift, inner hex screw plug on each side of small
housing shell, and screw inner hex screw plug (see Figure 3-219), install centering seat ring,
spacer ring, centering spring (low shift side) (see Figure 3-220), use bolt to connect small
housing end cover (range shift side) and small housing shell; there is end cover bush
between small housing end cover (range shift side) and small housing shell, the bolt
tightening torque is 21-25Nm.

Figure 3-219 Figure 3-220

⑧ Install sensor top pin and pressure switch, its torque is not more than 35Nm (see Figure 3-
221), each pressure switcher can take reference Figure 3-96; lay seal glue of bowl-style
 shim, then install it to the hole on the small housing shell and ensure not oil leakage (see
Figure 3-222); if not installation shift-choice support axle, then install it.

Figure 3-221 Figure 3-222

⑨ Use connection bolt to install double H valve and paper washer onto the small housing
shell, its torque is 21-25Nm (see Figure 3-223).

Figure 3-223

After installation small housing assembly, test the shift gear and examine whether it is
reliable and returning normal or not.

Section V Dismantle the Small Housing Assembly of HW18710 and

HW14710 Transmission

I. Dismantle the Small Housing Assembly

① Loose locking nut on the shift swing arm, dismantle shift swing arm and anti-dust cover
(see Figure 3-224); dismantle pressure switcher, sensor top pin, air pipe, two five-way valve
assembly, cut-off valve, air plug (see Figure 3-225).

Figure 3-224 Figure 3-225

② Unscrew the bolt connected small housing end cover (swing arm side) and small housing
 shell, take off small housing end cover (swing arm side), and oil seal and complex bush in
the small housing end cover (swing arm side) is not need to be dismantled; if it is damaged,
then need destroyed dismantle, but not permit to damage the interface of small housing end
cover (swing arm side) (see Figure 3-226); use punch to punch off elastic column pin
connected sensor drive ring, take off sensor drive ring, sector locking block and drive pin
(see Figure 3-227).

Figure 3-226 Figure 3-227

③ Dismantle the bolt connected small housing end cover (range shift side) and small housing
shell, take off small housing end cover (range shift side) (see Figure 3-228).

Figure 3-228 Figure 3-229

④ Take off rolling needle of the locking pin axle, then the locking pin axle and locking spring
(see Figure 3-229); dismantle bowl-style shim, and use punch to punch off the column pin
connected shift head and shift head (see Figure 3-230).
⑤ Dismantle spacer bush, shift axle assembly, fork, and interlocking fork in turn (see Figure 3-
231); in generally, the complex bush and bush on the small housing shell need not
dismantle; if damaged, use punch to punch it off, but not damage the small housing shell;
dismantle clamp spring on the shift axle assembly by use circlip pliers, then the centering
ring and spring can be dismantled.

Figure 3-230 Figure 3-231

II. Installation of Small Housing Assembly
① Install complex bush in the small housing end cover (swing arm side) (see Figure 3-222),
use special tool G11, G12 to install oil seal on inside and outside end cover (see Figure 3-
233, 3-234, 3-235).

Figure 3-232 Figure 3-233

Figure 3-234 Figure 3-235

② Install complex bush into the small housing shell and to its position (see Figure 3-236), and
lay suitable grease on the inner hole of complex bush; lay Locitite 680 bond on the bush and
ensure to cover all the column face, and spray Locitite 7649 bond, and then install it into the
small housing shell to its position (see Figure 3-237).

Figure 3-236 Figure 3-237

③ Assemble shift axle assembly: install centering spring, centering seat ring, and another
centering seat bush on the shift axle, compress spring on the elastic barrier ring (see Figure
3-238, 3-239).
 Figure 3-238 Figure 3-239

④ Put interlocking fork and shift head into the small housing cover, pass shift axle assembly to
inner holes of interlocking fork and shift head and install shift column pin to its position
(see Figure 3-240, 3-241); use punch to punch off the two end of column pin of shift head to
ensure the pin connection is firm and reliable (see Figure 3-242).

Figure 3-240 Figure 3-241

⑤ Put locking spring into the locking spring hole of small housing shell, pass locking pin axle
(cone end of locking axle outward side of swing arm) through pin hole and spring barrier
chip and locking spring, then put on needle (notice barrier chip direction) and keep the
rolling needle clamp on the groove of barrier chip; install drive pin to its position, put on
sector locking block and let locking pin axle clamp to the groove of sector locking block;
install sensor drive ring (notice direction: HW18709 is as Figure 3-244 shown), and then
locate it by use elastic column pin.

Figure 3-242 Figure 3-243

 Figure 3-244 Figure 3-245

⑥ Lay full of grease on the open of oil seal on small housing end cover (swing arm side),
fasten small housing end cover (swing arm side) on the small housing shell by connection
bolt; there is paper washer between small housing end cover (swing arm side) and small
housing shell, the connection bolt torque is 21-25Nm (see Figure 3-245); install anti-dust
cover, shift swing arm to its positions, and screw locking nut. The central line of short arm
of shift swing arm (see Figure 3-246 inner circle part) is vertical to the surface of small
housing.

Figure 3-246 Figure 3-247

⑦ Put spacer bush on the side of small housing shell (see Figure 3-247), use bolt to connect
small housing end cover (range shift side) and small housing shell; put on single clamp
shim, and there is end cover bush between small housing end cover (range shift side) and
small housing shell, the bolt tightening torque is 21-25Nm (see Figure 3-248).

Figure 3-248 Figure 3-249

⑧ Install sensor top pin and pressure switch, its torque is not more than 35Nm (see Figure 3-
249), each pressure switcher can take reference Figure 3-96; lay seal glue on bowl-style
shim, then install it to the hole on the small housing shell and ensure not oil leakage (see
Figure 3-250); if not installation shift-choice support axle, then install it.
 Figure 3-250 Figure 3-251

⑨ Use connection bolt to install cut-off valve, two-position five-way valve assembly and paper
washer onto the small housing shell(see Figure 3-251,3-252), M4 bolt tightening torque is
2-3Nm, M6 bolt tightening torque is 9-11Nm, M8 bolt tightening torque is 21-25Nm .

⑩ Connect air pipe with cut-off valve and two-position five-way valve, the connection method
is as Figure 3-253,3-254 shown, and then screw the nut to ensure the joint not air leakage.

Figure 3-252 Figure 3-253

Figure 3-254 Figure 3-255

Use single clamp shim to fasten air pipe to its position as Figure 3-255 shown; and finished
small housing assembly is as Figure 3-256 shown.
 Figure 3-256

After installation small housing assembly, test the shift gear and examine whether it is
reliable and returning normal or not.

Section VI Repairing Tool for HW Series Transmission

The maintenance tools, repairing HW series transmission made by Sinotruck, is supported by
Jinan Tanaka Commerce Co., Ltd., there are shape and use method as followings:
1. Labor-saving Wrench (G01).
Connected bolt of HW series transmission output flange nut is tightened by 1260Nm. When
dismantle or tightening, even use extension lever is also difficult. Especially dismantle on-
sit; it is more difficult to remove it. Such as Figure 1a, flange nut labor-saving wrench is
made up of multi power, multi power support, flange nut collet head, slide bar, slide head
and wrench level. Multi power is one kind of planet gear multi power that is input 1Nm
torque, and output 4.5Nm torque. Such as Figure 1b, firstly, When the removal of the flange
nut, place the collet head (G14) of S=60mm on the flange nut, and then use two flange bolts
to fix the support on the flange of the transverse gear. Insert the square output end of the
multi power into the collet head, and insert the hexagonal of the multi power body into the
inner hexagonal of the support and then fix the multi power on the support. Apply the
ratchet wheel spanner or guide bar head and wrench lever to turn the input end of multi
power in the unscrewing direction, and then remove the flange nut smoothly

Figure 1a: Flange Nut Labor-saving Wrench Figure 1b: Removal/Installation Operation of Flange Nut
Using the Labor-saving Wrench

2. Hanging Scaffold of Supplementary Gearbox (G02)

Figure 2a is hanging scaffold of supplementary gearbox. When repairing and dismantle the
transmission and separation main gearbox and supplementary gearbox, use this device is
very convenient.

Before dismantle transmission, firstly use labor-saving wrench to dismantle flange bolt, then
 pull out of the oil seal plug from the hole of output shaft, then dismantle the fastening nut of
main axle in the output shaft hole by extension bar, and then install it by flange bolt .

Such as Figure 2b, use two flange bolts to fasten the hanging scaffold and output flange nut
of transmission. Use hanging scaffold to erect the transmission assembly.(notice: when
erecting the transmission, use wood block to pad the transmission housing, and let input one
axle suspending to prevent it damage).

If supplementary gearbox needs to be dismantle, firstly, unscrew the bolt connected main
gearbox and supplementary gearbox, and confirm that the fastening nut of main axle in the
center hole of output shaft has been dismantled (this is very important, if the fastening nut is
not dismantled previously, separate main gearbox and supplementary gearbox by force will
damage the main axle). And then use two M10 top threads to separate supplementary
gearbox assembly from the housing of main gearbox, such as Figure 2c, use hanging
scaffold to separate supplementary gearbox from the main gearbox.

Figure 2a: Hanging Scaffold of Supplementary Gearbox Figure 2b: Lifting up the Transmission Assembly by
Hanging Scaffold.

Figure 2c: Lifting up and Dismantle Supplementary Gearbox by Hanging Scaffold

3. Extractor (G03) of Planet Supporter Bearing (G020)

Extractor is made up of two semicircle clipping bushings, support board, top thread of the
ejection screw, clipping bushing and others (as shown in Figure 3a). Firstly clip the two
semicircle clipping bushings of the extractor on the bearing respectively, tighten the two
semicircle clipping bushings with fixing sleeve, secure the support board on two tie rods,
and block the round end cap at the end of the shaft tube. Tighten the ejection screw to stand
 the top thread of the ejection screw to the middle of the end cap. Use the spanner to tighten
the ejection screw so as to disassemble the bearing in intact way (As shown in Figure 3b).

Figure 3a: Extractor of Planet Supporter Bearing Figure 3b: Pull out of Planet Supporter Bearing by Extractor.

4. Extractor of High Shift Cone-hub and Synchronizer Gear Seat (G04).

Due to high shift cone-hub of supplementary gearbox is hotly equipped in the output shaft;
it must be used special tool to extract it out in normal temperature. As shown in Figure 4a,
extractor is made up of two semicircle head, board, clipper, plate and top thread and 20 ton
hydraulic Rama. When dismantle, firstly put extracting plate, bar and hydraulic Rama on
the high shift cone-hub, then let the two semicircle extracting head clipping on the high shift
cone hub flange. Notice: there is a circle groove on the front end of extracting head, let the
upward flange of cone-hub round plate clip the flange of high shift cone-hub, at last, put the
top board on the center hole of output shaft. Turning the hydraulic Rama, let its top head
prop up the center of board. There is a black switcher on the hydraulic Rama, tightening
screw, and use lever to press Rama column plug up and down, and the high shift cone-hub
will be smoothly pulled out. Then unscrew the Rama button, the piston can automatically
retract. Extracted high shift cone-hub is as shown in Figure 4c. When dismantle high shift
cone-hub, pay attention to not draw the cone-hub to slanting.
Use the same extractor and adopt the same method can dismantle synchronizer gear seat.
Before dismantle, firstly, dismantle the elastic barrier ring from the synchronizer gear seat,
then lift up the synchronizing ring under the gear seat, let the two semicircle extracting head
clip the gear seat and cone-ring, and clip sleeve locate on the extracting head, press the
column plug of hydraulic Rama, gear seat and synchronizing ring can be smoothly extracted
out.
Notice: hydraulic Rama piston only has 50mm long, therefore, each extracted distance is
not more than 40mm. if the extracting distance is not enough, then turning the Rama knob
let the piston of Rama retract, and then entirely turning Rama, let the Rama piston re-prop
up the top board. If the Rama moving distance is still not enough, it can be changed and
connected longer top board.
 Figure 4a: Extractor of High Shift Cone-hub Figure 4b: Use Extractor to Dismantle Synchronizer High
Shift Cone-hub or Synchronizer Gear Seat.

Figure 4c: Dismantled High Shift Cone-hub Figure 4d: Dismantled Synchronizer Gear Seat

5. Extractor(G05) of front and back Bearing of Auxiliary Shaft.

When dismantle auxiliary shaft of main gearbox, and need change front and back bearing of
auxiliary shaft, it can be dismantled by extractor. Due to front and back bearing have the
same size (only difference is the front bearing has snap ring groove, but the back bearing
has not), so it can only use one extractor to remove it.
Before dismantle, firstly remove the snap ring (front bearing), then let the two semicircle
extracting plate clip on the bearing flange bottle, put clip sleeve on the extracting plate for
locating, fasten extracting bar and top thread on the two rods, tighten screw top thread (as
shown in Figure 5b is dismantling back bearing without snap ring), the bearing can be
smoothly extracted out.

Figure 5a: Extractor of Bearing on Auxiliary Shaft Figure 5b: Dismantle Front and Back Bearing by
Extractor.

6. Extractor of Idle Wheel Axle (G06)

As shown in Figure 6a, idle wheel axle (middle axle of reverse shift) extractor is made up of
handle, extracting bar, and glide hammer. When dismantle reverse shift middle axle, firstly
screw the thread of M12 of front end on extracting bar to the center thread hole of middle
axle of reverse shift, then as shown is Figure 6b, continuously lift up the glide hammer, let
the glide hammer up-thrust the handle for smoothly pulling out the middle axle of reverse
shift.
 Figure 6a: Extractor of Idle Wheel Axle Figure 6b: Use Extractor to Dismantle
(Middle Axle of Reverse Shift) Middle Axle of Reverse Shift.

7. Snap Ring Pliers (G07)

Due to there are lot of non-standard snap ring equipped in the transmission, it needs special
pliers to carry on dismantle and install. As shown in Figure 7b, it is used snap ring pliers to
dismantle exterior snap ring of input one axle bearing.

Figure 7a: Special Snap Ring Pliers Figure 7b: Dismantle and Install Snap Ring by Snap Ring
Pliers

8. Extractor(G08) of Input shaft Bearing (6213N).

When change and dismantle bearing of input shaft (one axle) without disassembly the
transmission, the extractor of input shaft (one axle) can be used. As shown in Figure 8a,
extractor is made up of extracting plate, extracting bar, top thread and two extension
supporter bar. Before dismantle, firstly, dismantle the inside and outside snap ring from the
input shaft (one axle), use copper bar thrust the front housing of transmission, let the
bearing out of a little bit, put the two semicircle extracting plate clip on the snap ring groove
of bearing, put the clipper sleeve on the extracting plate for locating, then install two
extension supporter bar, extracting plate and top thread, then screw the top thread, the
bearing can be smoothly extracted out.
Figure 8a: Extractor of Input shaft (One Axle) Figure 8b: Dismantle Bearing of Input shaft (One Axle)

9. Tube Processor (G09)

When re-assemble the planet supporter assembly, as shown in Figure 9b, use tube processor
and copper hammer to thrust planet supporter, let the planet to get to its position. This tube
processor can also be used to thrush and install bearing of input shaft (Figure 9c) and
odometer worm ring (Figure 9d).

Figure 9a: Install Tube Processor Figure 9b: Use Tube Processor to Install Planet
Supporter to its Position

Figure 9c: Use Tube Processor to Install Figure 9d: Use Tube Processor to
 Bearing of Input shaft Install Odometer Worm

10. Press Plate of output shaft Oil Seal (G11)

As shown in Figure 11a, this is press plate of output shaft oil seal. When install oil seal of output
shaft, firstly put oil seal into the plate, and then use press plate to push the oil seal into the end
cover of output shaft (as shown in Figure 11b)

Figure 11a: Press Plate of Output shaft Oil Seal Figure 11b: Install Output shaft Oil Seal by Using
Press Plate.

11. Punch Bar of Interior Oil Seal of Small End Cover (G12)

There are installed interior and exterior oil seals on the small end cover of shift housing of
transmission level. As shown in Figure 12b, when installing, put the interior oil seal on the
end of punch bar, then press the interior oil seal into the small end cover by punch bar.

Figure 12a: Punch Bar of Oil Seal in Small End Cover Figure 12b: Use Punch Bar to Install Interior Oil Seal
of Small End Cover

12. Punch Bar of Exterior Oil Seal of Small End Cover(G13)

As shown in Figure 13b, put the exterior oil seal at the end of punch bar, and then press the
exterior oil seal into the small end cover by using punch bar.
 Figure 13a: Punch Bar of Oil Seal in Small End Cover Figure 13b; Use Punch Bar to Install exterior Oil
Seal of Small End Cover

14. Flange Bolt (S=60mm) Tube Processor (G14)

Output flange nut is fastened by exterior hex flange bolt which opposite side is S=60mm,
output flange tube processor, as shown in Figure 14a, is a special interior hex tube processor
which can be used by pneumatic pick (pneumatic wrench), also can be used extensive lever,
and cooperated with labor-saving wrench at the same time.

Figure 14a: Tube Processor of Flange Nut Figure 14b: Use Tube Processor of Flange Nut to Dismantle
Extensive lever

15. Measuring Plate (G15)

In order to guarantee the axial stability of main axle, during repairing when change the
following parts, such as the main axle assembly with ball head, middle housing of
transmission, planet supporter assembly in supplementary gearbox assembly, 61820
bearing, 63/22 bearing, spacer bush, high shift cone-hub assembly, oil guide ring assembly,
back housing of transmission and others, the precise size from three-shift gear end to front
end of main gearbox housing must be measured to ensure the thickness of the axial
adjustable pad of main axle. As shown in Figure 15a, this is special measuring plate.
Notice: on the upward surface of the measuring plate, there are precise sizes of measuring
plate thickness. When measuring, firstly, put the middle housing pre-install on the
supplementary gearbox assembly and to its position.
As shown in Fig 15b, install a pre-chosen adjustable pad on main axle (in order to prevent
adjustable pad and hex key dropping down, lay grease on the interface and let them stick on
the main axle), then put the spline of main axle assembly on the sun wheel spline of
supplementary gearbox assembly and to its position. Let one face with thickness marks
upward, and pin hole of two side of measuring plate on the locating pin of end surface
housing, insert the tightening bolt of main axle into the center hole of measuring plate, then
put a paper washer sealed middle and front housing on the plane of measuring hole, and
then measure the distance from the sealed paper washer to pointed gear upward end by
using depth rule through measuring hole.
 Figure 15a: Measuring Plate Figure 15b: Use Measuring Plate to Measure the Adjustable pad
Thickness of Main Axle.

16. Flange Nut Extractor (G16)

Before disassembly the transmission, it always needs to remove the flange nut of output
shaft. As shown in Figure 16a, flange nut extractor actually is made up of a 10 ton hydraulic
Rama, extracting top board and two extracting bars, among them one end of the two
extracting bar is fastened on the extracting board by M18 nut, another end is inner thread
hole of M14. as shown in Figure 16b, firstly, remove the flange nut and washer board, then
put the top board on the center hole of output shaft (notice: top board shall not damage the
pin located output shaft and washer board), then use symmetry M14 bolt on the flange to
link the two extracting bars, turn hydraulic Rama and let its top head prop up the center of
board, and then screw the Rama knob tighten, and use lever to press Rama column plug up
and down, the flange shall be smoothly pulled out. Notice: when connected the flange bolt
and two extracting bars, the two bars shall have the same length, otherwise, the flange will
be pulled slanting.

Figure 16a: Flange Extractor Figure 16b: Use Extractor to Dismantle Flange

This extractor can share a 10 ton hydraulic Rama and extracting board with high shift cone-
hub extractor.
17. Extractor(G17) of Output shaft Bearing (6218)
When dismantle the planet gear wheel device of supplementary gearbox, it firstly needs to
remove sensor worm ring and bearing (6218) of output shaft of odometer. If bearing and
worm ring joint too close, it must be used special extractor to dismantle. As shown in Figure
17a, this is a extractor of this bearing. As shown in Figure 17b, before dismantle, firstly, put
the semicircle extracting head clip to the bearing, the ring ridge of extracting head shall be
clipped the clearance of bearing and end cover. Then put the clipper sleeve on the extracting
head, use 10 tons hydraulic Rama and extracting board to fasten it by two extracting bars,
then turn hydraulic Rama, let the top head of Rama prop up the extracting board of center
hole of output shaft, screw the knob firmly and press column plug by lever, the bearing of
output shaft can be smoothly pulled out.
Figure 17a: Extractor of Output shaft Bearing Figure 17b: Dismantle Output shaft Bearing by Extractor.

Important Points of this Chapter.

Master the repairing methods and notices of HW18709、HW18710、HW14710、HW20716 series
transmissions, comprehend all different structure and principles of HW series transmissions and its
repairing tools and application methods.

Exercises:
1． What’s requirements when assemble end cover of auxiliary axle, end cover of input shaft, oil
pump assembly, and if not according to these requirements, what’s the caused results?
2． What are the Mechanic lubrication parts in HW transmission? and description the oil route.
3． Before dismantle supplementary gearbox assembly, what shall be noticed?
4． Why need add locking device of range shift in supplementary gearbox of HW18710 series
transmission? And which parts included in the locking device?
5． What problems shall be noticed when assemble the supplementary gearbox?
6． Why need to carry on the measurement of adjustable pad of main axle? Which parts needs to
be re-measured when they are changed? What caused result when not measuring or
measuring not precise?
7． Description the measuring method of adjustable pad of main axle.
8． Why double supplementary axle structure needs align to teeth? How to align? What’s result
if wrong align to teeth?
9． Why firstly screw a M16 hollow bolt in the bottom of the front housing before installing HW
transmission assembly?
10． What’s difference from (left) supplementary axle and (right) supplementary axle? What’s use
for its structure?
11． What special structure adopted by Fuller transmission for PTO in neutral position? Is there
this special structure in the HW transmission for PTO in neutral position?
12． What difference of interlocking device of main gearbox and supplementary gearbox of
HW18710 from HW18709?
13． How to adjust the adjustable pad of input and output shaft? What’s advantage to adjust the
shim?
14． What’s the axial clearance between each gear of main axle assembly of HW transmission?
15． What are the kinds of adjustable pad of HW transmission? And description them.
16． What are the requirements when assemble cylinder of range shift and insert and split
cylinder?
17． Why lay grease on the open mouth of oil seal when it installing?
18． What are the requirements when installing the sensor drive ring? Why HW18710 is different
from HW 20716?
19． What are the repairing tools and methods of HW series transmission?