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Engine JAC HFC4DA1-2C. Manual - part 124

MT Manual

Manual

Manual Transmission

Transmission

-16-

Instruction

Instruction and

and

and Operation

Operation

SUNRAY vehicles adopt synchronizer manual-shift mechanical transmissions of good shifting flexibility, good hand
feel, low noise, compact structure, large carrying capacity as well as good sealing performance, which consist of five
forward gears and one reverse gear. All gears are of helical teeth. Except for the reverse gear that adopts direct
transmission through sleeve, the other gears adopt

three-cone (single cone, three-cone only for 1

gear)

synchronizer

. Shifting mechanism is of cable-type remote control.

Principles of motion:
1

gear

Engine→Clutch→Input shaft 1→Main gear of countershaft 15→Countershaft 11→

driving gear

6→1st/2nd gear

synchronizer 5→Output shaft 10
2

gear

Engine→Clutch→Input shaft 1→Main gear of countershaft 15→Countershaft 11→2

driving gear

4→1st/2nd gear

synchronizer 5→Output shaft 10
3

gear

Engine→Clutch→Input shaft 1→Main gear of countershaft 15→Countershaft 11→3

gear of countershaft 14→3

driving gear

3→3rd/4th gear synchronizer2→Output shaft 10

gear

Engine→Clutch→Input shaft 1→3rd/4th gear synchronizer 2→Output shaft 10
5

gear

Engine→Clutch→Input shaft 1→Main gear of countershaft 15→Countershaft 11→5

gear of countershaft 12→5

driving gear 9→5th/reverse gear synchronizer 8→Output shaft 10
Reverse gear
Engine→Clutch→Input shaft 1→Main gear of countershaft 15→Countershaft 11→Reverse gear 13→Reverse driving
gear 7→5th/reverse gear synchronizer 8→Output shaft 10

MT Manual

Manual

Manual Transmission

Transmission

-17-

Instruction

Instruction and

and

and Operation

Operation

Control

Gear selector lever and gear shift lever can be controlled
through controlling the control handle inside cab to
realize gear shifting. Different directions shown on the
control handle grip corresponds to different gear select
and shift positions. The control handle shall return to
neutral position automatically after each time of gear
removal. Gear selection can only be performed after the
control handle is returned to the neutral position.
1.

In order to shift gear, depress the clutch pedal fully
to make the transmission out of engine torque and
then control the gear shift lever quickly to shift
gear. Please adopt low speed gear when starting.

Please adopt low speed gear during vehicle
climbing, running downhill or turning. Don’t let
the vehicle idling with clutch released.

In case it is difficult to control the control handle,
please stop and inspect. Don’t apply it violently.

Kilometers

Kilometers applicable

applicable

applicable to

to each

each

each forward

forward

forward gear

gear

gear of

transmission:

Gear

Position

gear

Kilometers

0～15

20～30

35～45

50～60

65～75

Attention:

Gear

shifting

transmission

should

performed

performed within

within

within relevant

relevant

relevant kilometer

kilometer

kilometer range.

range.

The

The applicable

applicable

applicable kilometers

kilometers

kilometers may

may

may vary

vary

vary when

when

when the

the

transmission

transmission is

is equipped

equipped

equipped to

to different

different

different vehicles.

vehicles.

Principle

Principle of

of gear

gear

gear shifting

shifting

Under the forward running status, the requirements of
gear shifting is as follows: gear shifting from 1

gear to

gear step by step for speeding up, gear shifting from

gear to 1

gear step by step for speeding down;

reverse gear can be shifted to in 3 seconds of pause after
the clutch pedal is depressed under motionless state of
vehicle; don’t apply reverse gear under running state
and don’t apply forward gears under reversing state.
Don’t use the control handle of transmission as an
armrest, in order to avoid early wear of shift fork.
Attention:

Attention:

Attention: In

In case

case

case of

of any

any

any emergency

emergency

emergency occurs

occurs

occurs during

during

running

running state,

state,

state, you

you

you may

may

may perform

perform

perform gear

gear

gear shifting

shifting

without

without following

following

following this

this

this principle

principle

principle....

Meaning

Meaning of

of transmission

transmission

transmission name:

name:

Inspection

Inspection and

and

and Confirmation

Confirmation

Check input shaft assembly

Check input shaft for gear teeth fracture, pitting,
severe wear or scuffing of tooth surface. If any,
please replace the input shaft.

Check input shaft spline for any severe wear or
damage. If any, please replace the input shaft.

Rotate bearing by hand to check for non-flexible
rotation or sticking. If any, please replace the

bearing.
Note:

Note:

Please check the stop ring on bearing during
replacement of bearing. If it is deformed, please
replace it.

Check output shaft assembly
Check input shaft for gear teeth fracture, pitting,
severe wear or scuffing of tooth surface. If any,
please replace the output shaft.
Note:

Note:

Rotate bearing by hand to check for non-flexible
rotation or sticking. If any, please replace the
bearing.

Check synchronizer ring

Check tooth surface of synchronizer ring for any
damage.

Check conical surface for any damage or wear;
check if the screw is crushed.

When the synchronizer ring is pressed close to gear,
check clearance “A”. If “A” is below the limit,
please replace the ring.

Limit

Limit value:

value:

value: 0.5mm

0.5mm

Check synchronizer gear sleeve and gear hub

Assemble the synchronizer gear sleeve and gear
hub together and check for smooth sliding but no
sticking.

Check front and read end of inner surface of gear
sleeve for any damage.

Attention: In case the synchronizer gear sleeve or gear
hub is in need of replacement, they should be replaced
as a whole.

Torque 280N.M (actual torque up to 300N.M)

Synchronizer structure

Five forward gears

Six gears

Synchronizer ring

Gear

MT Manual

Manual

Manual Transmission

Transmission

-18-

Instruction

Instruction and

and

and Operation

Operation

Fault

Fault diagnosis

diagnosis

Common

Common fault

fault

fault diagnosis

diagnosis

diagnosis table

table

Fault Symptom

Possible Cause

Solution

Jumping

back

neutral

position under running state

Excessive wear of shift fork shaft arc,
elastic deformation of lock ball spring

Check if the operating system has pushed the gear
shift rocker arm of transmission into place; or with
the transmission removed, push the shift fork into
gear by hand to check gear meshing status.

Excessive wear of shift fork working face

In case of incomplete meshing, please check shift
fork for deformation or working face excessive wear.

Excessive wear of joint surface of shift fork
gear ring or gear sleeve

In case of complete meshing, please check wear
condition of inverted cone of gear sleeve and
engaged gear.

Axial looseness of gear

If excessive clearance is felt, please check fork shaft
groove and guide spring for any wear or failure.

Difficulty in gear shifting, loud
impact sound in gear shifting,
or

difficulty

shifting

certain

gear

with

normal

operation of clutch

Severe wear of synchronizer ring

Replace synchronizer ring.

Noise generated in transmission

1. Regular impact sound

2. Uniform noise

Caused by breakage of individual gear
tooth

Check relevant part and remove it.

Backlash increase or gear damage

Remove, check and clean or replace damaged gear.

Bearing wear

Remove, check and clean or replace damaged
bearing.

Insufficient lube oil

Change oil or add new oil.

Oil leak

Adding too much oil, too high oil level

Remove oil filler plug to check oil level.

Excessive wear or damage of oil seal

Replace oil seal.

Uneven application of sealant or damage of
sealing paper pad

Remove parts relevant to each joint surface and
apply sealant evenly, or replace paper pad.

Failure of vent plug

Replace vent plug.

Joint surface bump not shaved in time

Remove parts relevant to each joint surface to have
the bump point shaved.

Abnormal spoilage of bearing

Too dirty lube oil

Change oil.

Inadequate lubrication or nonconforming or
inferior

lube oil

Check oil level, add or change oil.

Unqualified bearing adopted

Replace bearing.

MT Manual

Manual

Manual Transmission

Transmission

-19-

Removal/Installation

Manual

Manual transmission

transmission

Remove manual transmission.

●

Oil drainage

Attention:

Remove oil drain plug with

wrench and drain oil through this plug instead
of other parts.

Remove release bearing from input shaft front cap.

Remove input shaft front cap from transmission.

Remove clutch housing.

Attention: If the transmission housing is assembled
tightly with clutch housing, a rubber hammer or
copper rod can be applied to knock on the housing
edge to make them become loose.

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