Hyundai 20D-7SA User manual

1
Introduction
This manual main introduces the items in the aspects of performance, structure, and
operation, as well as maintenance and service, etc of the 2t-3.5t forklift trucks, so that the
operators are able for a correct use and maintenance.
During the user operating process, the operators and equipment management personal
involved shall carefull follow the relevant regulations of this manual, for the forklift truck to
maintain its good technical conditions.

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Table of Contents
Introduction ........................................................................................ 1
I. Forklift Truck Main Technical Parameters ................................................ 4
II. Description about Forklift Truck Main Parts .....8
III. Structure, Principle, Adjustment, and Maintenance of Forklift Truck .......... 10
. Power System ................................................................................ 10
1.1 Engine Overview ............................................................................. 10
1.2 Items to be Observed for Installation & Operation of Engine(LPG/Gasoline) ...... 13
1.3 Engine Adjustment .......................................................................... 15
1.4 Fuel S stem: ................................................................................. 16
2. Clutch and Its Pedal ......................................................................... 21
2.1 Overview ...................................................................................... 24
2.2 Method for Replacement of Brake Shoe Assembl .................................... 24
3. Hydraulic Transmission Case and Torque Converter ............................... 26
3.1 Overview ...................................................................................... 26
3.2 Torque Converter ............................................................................ 28
3.3 H draulic Clutch ............................................................................. 29
3.4 Control Valve, Safet Valve, and Inching Valve ......................................... 30
3.5 Transmission Case .......................................................................... 31
3.6 Oil Feed Pump ............................................................................... 31
3.7 H draulic Oil Circuit (H draulic Transmission) .......................................... 32
3.8 Speed Reducer and Speed Differential .................................................. 33
3.9 Traction of Forklift Truck to be Repaired .................................................. 33
3.10 Oil Port Joint Positions .................................................................... 33
4. Drive Axle ...................................................................................... 34
4.1 Overview ...................................................................................... 34
4.2 Maintenance of Drive Axle ................................................................. 35
5. Steering System ............................................................................. 36
5.1 Overview ...................................................................................... 36
5.2 Examination after Reassembl of Steering S stem .................................... 38
5.3 Failure Removal for Steering S stem .................................................... 39
6. Cross Cylinder Drive Axle ................................................................. 40
6.1 Overview ...................................................................................... 40
6.2 Steering Knuckle and Steering King Pin ................................................. 42
6.3 Adjustment for Pre-Tightened Load of Steering Wheel Bearing ..................... 42
7. Brake System ................................................................................. 43
7.1 Overview ...................................................................................... 43
7.3 Wheel Brake .................................................................................. 44
7.4 Automatic Clearance Regulator ........................................................... 46
7.5 Parking Brake ................................................................................ 46

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7.6 Adjustment of Brake Pedal (Mechanical Forklift Truck).................................46
7.7 Adjustment of Brake Pedal (Hydraulic Forklift Truck) ...................................48
7.8 Maintenance ...................................................................................48
7.9 Operating Test on Automatic Clearance Regulator .....................................54
7.10 Failure Removal for Wheel Brake.........................................................55
8. Hydraulic System.............................................................................56
8.1 Overview .......................................................................................56
8.2 Main Oil Pump.................................................................................57
8.3 Multi-way Valve and Bypass Valve .........................................................57
8.3.1 Operation of Spool Valve..................................................................58
8.3.2 Main Safety Overflow Valve and Bypass Safety Valve ...............................58
8.3.3 Action of Inclined Autolock Valve.........................................................59
8.4 Oil Circuit of Hydraulic System (Main Oil Circuit) .......................................60
8.5 Lifting Cylinder ................................................................................61
8.6 Limiting Valve ..................................................................................62
8.7 Tilting Cylinder.................................................................................63
8.8 Maintenance of Main Oil Pump.............................................................64
9. Lifting System .................................................................................72
9.1 Overview .......................................................................................73
9.2 Inside and Outside Masts ...................................................................73
9.3 Bracket..........................................................................................73
9.4 Adjustment of Lifting System ...............................................................73
10. Electrical System............................................................................74
10.1 Overview......................................................................................74
10.2 Operating Brief Description................................................................74
IV. Drive, Operation, and Routine Maintenance of Forklift Truck.......................... 75
1. Conveyance of Forklift Truck..................................................................76
2. Storage of Forklift Truck .......................................................................76
3. Preparation prior to Operation................................................................76
4. Operation of Forklift Truck.....................................................................76
5. Notices for application of Cooling System..................................................77
6. Oils Used for Forklift Truck ....................................................................78
7. Lubricating System Table .....................................................................79

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I. Forklift Truck Main Technical Parameters (Refer Table Diesel F/L & LPG/Gasoline F/L)
Main Technical Parameters
Diesel F/L
Model
Parameter
20D-7SA 25D-7SA 30D-7SA 35D-7SA
+Performance Parameter
Rated Load (KG) 2000 2500 3000 3500
Load Center (mm) 500
Lifting Height (mm) 3000
Free Lifting Height (mm) 160 165 170
Mast Tilt Angle (Front/Rear) 6/12
Lifting
Speed
(mm/s)
No-Load 550 550 440 350
Full-Load 530 530 425 335
Running
Speed
(km/h) Forward 20 20 19 18
Max
Traction
Force
No-Load (N) 15000 1700
Full-Load (N) 17000 1900
Gradeabilit
No-Load (%) 20 18
Full-Load (%) 20 18
Min Turning Radius R (mm) 2330 2330 2450 2510
Min Cross Passage Width K (mm) 1940 2010 2140 2160

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Main Technical Parameters
Diesel F/L Continued
Model
Parameter
20D-7SA 25D-7SA 30D-7SA 35D-7SA
Size Parameter
Whole Length L (Without Fork) (mm) 2590 2590 2705 2790
Whole Width W (mm) 1150 1210
Whole Height D(Mast Retracted) (mm) 2010 2075 2150
Whole Height E(Mast Extended) (mm) 3990 4100
Wheelbase F (mm) 1600 1700
Wheel
Base
Front Q1 (mm) 970 1000
Rear Q2 (mm) 980
Front Clearance B (mm) 475 490 510
Rear Clearance C (mm) 515 515 580
Fork Dimension
Length (mm) 1070
Width (mm) 122 125
Height (mm) 40 45 50
Fork Horizontal Adjustment Quantit (mm) 250-1040 250-1100 260-1110
Ground Clearance(in the Place of Mast) (mm)
125 140
Self weight (kg) 3400 3700 4380 4730

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Main Technical Parameters
LPG/Gasoline F/L
Model
Parameter
20L-7SA 25L-7SA 30L-7SA 35L-7SA
Performance Parameter
Rated Load (kg) 2000 2500 3000 3500
Load Center (mm) 500
Lifting Height (mm) 3000
FreeLifting Height (mm) 160 165 170
Mast Tilt Angle (Front/Rear) 6/12
Lifting Speed
(mm/s)
No-Load 550 550 450 350
Full-Load 530 530 425 335
Running
Speed
(km/h)
Forward 20 20 19 18
Max Traction
Force
No-Load (N) 15000
Full-Load (N) 17000
Gradeabilit
No-Load (%) 20 18
Full-Load (%) 20 18
Min Turning Radius R (mm) 2330 2330 2450 2510
Min. Cross Passage Width K (mm) 1940 2010 2140 2160

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Main Technical Parameters
LPG/Gasoline F/L Continued
Model
Parameter
20L-7SA 25L-7SA 30L-7SA 35L-7SA
Size Parameter
Whole Length L (Without Fork) (mm) 2590 2590 2705 2790
Whole Width W (mm) 1150 1210
Whole Height D(Mast Retracted)(mm) 2010 2075 2150
Whole Height E(Mast Extended) (mm) 3990 4100
Wheelbase F (mm) 1600 1700
Wheel
base
Front Q1 (mm) 970 1000
Rear Q2 (mm) 980
Front Clearance B (mm) 475 490 510
Rear Clearance C (mm) 515 515 580
Fork
Dimension
Length (mm) 1070
Width (mm) 122 125
Height (mm) 40 45 50
Fork Horizontal Adjustment Q t (mm) 250-1040 250-1100 260-1110
Ground Clearance( Mast) (mm) 125 140
Service Weight (kg) 3320 3620 4300 4650

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II. Description about Forklift Truck Main Parts
Clutch
Drive Axle Steering S stem Steering Axle Lifting S stem
Brake and Clutch Control (Mechanical Truck)
Brake and Inching Control (H draulic Truck)
Control S stem Parking Brake H draulic S stem
Throttle Control/
Air Throttle Control
Electrical S stem
PowerS stem
Transmission
S stem Torque
Converter
Mechanical
Transmission
Case
H draulic
Transmission
Case
Speed
Reducer or
Speed Differential

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Outside Drawing of Forklift Truck

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III. Structure, Principle, Adjustment, and Maintenance of Forklift Truck
In order for operators to use, service, and maintain the forklift truck in a better wa , the items of such
aspects as the structure, principle, adjustment, disassembl and assembl , maintenance, and failure
removal, etc related to the forklift truck are now introduced one b one, respectivel .
. Power System
1.1 Engine Overview
Refer to Table 1 and Table 2 for the Diesel and LPG/Gasoline engines used at present for 2.0-3.5t forklift
trucks.

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Table 1
Main Technical Parameters Diesel Engine
Model Mitsubishi S4S
T pe 4-Stroke, Water-Cooling, Straight-Line
and Valve in Head
C linder
Number of C linders C linder
Diameter x Stroke (mm) 4-94×120
Total Displacement 3.331
Compression Ratio 22.1
Rated Power/Speed 35.3kw/22500rpm
Max Torque/Speed 182N.m/1800rpm
No-Load Min Speed (rpm) 770 20
Min Fuel Specific Consumption (g/ps.h) 265
Whole Length x Whole Width x Whole Height (mm) 781×567×717
Movement Direction Counterclockwise as viewed from fl wheel side
Firing Order 1-3-4-2
Valve Timing
Inlet Valve Open before Top Dead
Center(BTDC) 30
Inlet Valve Close after Bottom Dead
Center(ABDC) 50
Exhaust Valve Open before Bottom
Dead Center(BBDC) 74
Exhaust Valve Close after Top Dead
Center(ATDC) 30
Valve
Clearance
mm
Inlet Valve (Heat Engine) 0.25
ExhaustValve(Heat Engine) 0.25
Cooling S stem Forced Circulation Water Cooling
Lubricating S stem Forced Circulation
Main Part
Injection Pump Bosch A
Fuel Filter Catridge of Paper Element
Engine Oil Pump Trochoid
Oil Rough Filter Catridge of Paper Element
Water Pump Centrifugal T pe
Thermostat Wax Pellet T pe
Generator Voltage 12V
Current 50A
Starter Voltage 12V
Output Power 2.2kw
Batter
Voltage 12V
Capacit 90Ah
Referential Data
Lubricating Oil Capacit 10 (Oil Pan : 9 , Filter : 1 )
Cooling Water
(Engine Water Jacket) 5.5
Diesel Engine

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Table 2
Main Technical Parameters LPG engine
Model Nissan K25
T pe 4-Stroke, Water-Cooling, Straight-Line, and Valve
in Head
C linder
Number of C linders C linder
Diameter x Stroke (mm) 4-89×100
Total Displacement 2.488
Compression Ratio 8.7
Rated Power/Speed 37.4kw/2300rpm
Max Torque/Speed 176.5N.m/1600rpm
No-Load Min Speed 850rpm
Min Fuel Specific Consumption 290g/kw.h
Whole Length x Whole Width x Whole Height 708.9×588.6×728mm
Movement Direction In Clockwise Direction Looking from the
End of Fan
Firing Order 1-3-4-2
Valve Timing
Inlet Valve Open before Top Dead
Center(BTDC) 14
Inlet Valve Close after Bottom Dead
Center(ABDC) 30
Exhaust Valve Open before Bottom
Dead Center(BBDC) 32
Exhaust Valve Close after Top Dead
Center(ATDC) 12
Valve
Clearan
ce (mm)
Inlet Valve (Heat Engine) 0.38
Exhaust Valve(Heat Engine) 0.38
Cooling S stem Forced Circulation Water Cooling
Lubricating S stem Forced Lubrication
Main Part
Gasoline Pump Membrane T pe
Air Filter Paper Element Filter
Engine Oil Pump Gear T pe
Oil Rough Filter Paper Filtration
Water Pump Centrifugal T pe
Thermostat Wax T pe
Generator Voltage 12V
Current 50A
Starter Voltage 12V
Output Power 1.2kw
Batter Voltage 12V
Capacit 60Ah
Referential Data Lubricating Oil 3.5
Cooling Water 3.5
Refer to their respective engine operation and maintenance manuals for the introduction about
homemade engines used for 2.0-3.5 forklift trucks. The power of engine is mainl transmitted to the
transmission s stem from fl wheel through clutch or torque converter, and as engine itself carries
working oil pump, it is relativel convenient for engine to replace fan belt.
LPG/Gasoline ENGINE

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1.2 Items to be observed for Installation and Operation of LPG/Gasoline Engine
(1) Items to be observed for Installation of LPG/Gasoline Engine
Items to be Observed during Assembl
of Forklift Truck
Requirement Remarks
Cooling S stem
Allowed Temperature for
Cooling Water
80 in Common Use and
Max 110 (Outlet Water
Temperature)
To prevent too heated
engine
Pressure of Heat
Radiator C
over
88.3kPa(0.9kg/cm
2
) in
Common Use
Standard Value
Exhaust
Exhaust shall be performed
from the place of pet cock,
when coolin
g water is injected.
Lubricating
S stem Allowed Temperature 120 Max Oil Temperature
inside Oil Pan
(2)Items to be observed for Operation of LPG/Gasoline Engine
Items to be Observed during Operation
Requirement
Remark
s
Cooling S stem
Air Suction Negative
Pressure (Inlet Negative
Pressure of Inlet Bell
Mouth)
Max 6.18kPa, and
below 0.98kPa in
Common Use
It is required to use wire
mesh air filter core, to be
replaced generall after
work for 1200 hours in 6
months, while it shall be
replaced as soon as
possible for 3-shift
s stem or for atrocious
environment, and
otherwise, the c linder
and piston will be worn
out, and CO black smoke
will be discharged.
Exhaust S stem Exhaust Pressure
(Air Vent Outlet Pressure)
13.3kPa (below
100mmHg) in
Common Use
Adverse impact will arise
for engine power and
noise, if too high.
P.T.O
(Power-Take-Off)
S stem
Oil Pump Allowable Load 6.7kg mm/3215rpm
Otherwise P.T.O. chain
will extend and break and
engine will stall out.
Electrical
S stem Batter Capacit
Standard
Specification:
12V
-
60Ah
Generall used for
-15 +35
Operating
Environment
Ambient Temperature Standard Situation:
-15 +35
Regional Altitude
Standard
Specification:
Elevation below
1000m
When used at more than
1000m altitude, the
mixed compensation
shall be performed for
gasoline engines in
combination with
altitudes.

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(2)Fuel, Lubricating Oil Used for LPG/Gasoline Engines and Other Requirements
Item Requirement Remarks
Fuel
Lead-free general gasoline at 89 octane
rating to be used, equivalent to Number
JIS K2202-1988 2
Equivalent to Chinese Standard
GB484-86RQ-90 Number gasoline,
and otherwise, the rotating speed will
be instable, it will fail to combust
completel , if present with lead
gasoline, and will cause wear to parts
of gasoline engines, and give rise to
environmental pollution.
National engine use National
or above diesel
Lubricating Oil
Application Specifications: API: Above SD
Grade (Equivalent to above Chinese QD
Grade)
SAE: For Normal Regions: 20W
Clod Zones: 10W
To be replaced after use for 200 hours or
1 month
Switched to CF-4 level or above from
12th Ma , 2016
Anti-freezing
Fluid
(LLC-Long Life
Coolant)
Equivalent to JIS K2234-1988, 2 Kinds
LLC Concentration:
Standard Zones (above -15 ) 30%
Cold Zones (above -35 ) 50%
To be replaced generall for ever 2400
hours or 12 months, but it is changeable
b taking circumstances into
consideration, as operating environments
and conditions are different.
Chinese anti-freezing fluids shall be
referred to for implementation, and it is
recommended to use long-acting
antirust anti-freezing fluid (-35 )
Remark
Fuel
Filter
Authentic products to be used
To be replaced for ever 2400 hours or 12
months
Engine
Oil Filter
Authentic products to be used
To be replaced for ever 600 hours or 3
months
Air Filter
Authentic products to be used
To be replaced for ever 1200 hours or 6
months
Note: The period for replacement in the table indicates general situation (8 hours/da ), and it shall be
replaced earlier for 3-shift s stem or under atrocious operating conditions.

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1.3 Engine Adjustment
It is required to adjust the rotating speed of engine as it produces influence over operating efficienc with
both running speed and lifting speed of forklift truck, and the rotating speed of engine shall be adjusted
according to the undermentioned methods, if it fails to reach the specified value.
(1) Adjusting idle speed (used for LPG/Gasoline Engine)
a) Warm up the engine until the temperature of engine cooling water reaches 85 .
b) Mount tachometer on engine, and use the idle speed adjusting screw of carburetor to adjust the
engine speed to 650r/min for 2-3.5t forklift trucks.
c) Adjust the limit screw for the minimum openness of air throttle, in the direction for engine speed to be
increased.
d) Use idle speed adjusting screw of carburetor, to adjust the engine for 2-3.5t to 650r/min.
e) Repeat the steps c) and d) until a stable rotating speed of 650r/min.
(2) Adjusting the no-load maximum rotating speed (used for LPG/Gasoline Engine)
a) Warm up the engine until the temperature of engine cooling water reaches 85 .
b) Shut down, and ensure that the accelerator pedal is pushed down to the bottom and the air throttle is
full opened.
c) Start engine, and allow air throttle to be full opened.
d) The adjusting screw for speed limiter ma be turned until the specified speed is reached, if the rotating
speed of engine is higher or lower than specified value.
e) The maximum no-load rotating speed for 2-3.5t is 2800-3000r/min.
(3) Adjusting idle speed (Used for Diesel engine)
The speed of diesel engine is controlled b speed limiter of fuel injection pump, and the latter has been
properl adjusted on test bed in general, while it can no longer be adjusted after engine is mounted. The
steps for adjustment using test bed are given as follows (for reference):
Fig 1-1
a) Control the zero adjustment of gear rack, mount the control rack for measurement device onto the end
face of control rack for oil injection pump, and align the zero position of control rack for measurement
device with the zero position of graduated scale.
b) Full tilt the control rod in the direction for fuel to be increased, and ensure that the control rack
extends b more than 15mm. Then full tilt the control rod in the direction for fuel to be stopped, and
ensure that the control rack on the graduated scale is less than 1mm.
c) Adjust the oil injection timing and injection speed.

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d) Adjust the pressure from the minimum negative pressure.
(4) Examining whether or not air leak exists, b making use of adjusting rack to adjust the negative
pressure of oil injection pump in reference to Fig 1-2
(5) Adjusting the limit of smoke b making use of adjusting screw for limit of smoke, while the operators
shall pa attention that please never adjust it for imported engines, when the are basicall under normal
operating conditions.
Fig 1-2
1.4 Fuel S stem:
Fuel s stem is composed of fuel tank, oil quantit sensor, and oil quantit indicator (Fig 1-3 and Fig 1-4)
Full Level
Float to Rise to This Place
Float to Drop to This Place
Oil Drai Plug

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Fig 1-3 Fuel Tank (Diesel Forklift Truck)
Fig 1-4 Fuel Tank (LPG/Gasoline Forklift Truck)
Oil-Water Separator
Fuel Ta k
Full Level
Float to Rise to This Place
Float to Drop to This Place
Resista ce as 1
Oil Drai Plug E gi e Oil I let
Gasoli e Filter
Port Sealed up Fuel Ta k

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1.4.1 Fuel Tank
Fuel tank is an integrated welded structure connected with vehicle chassis into a whole, located on the
left side of vehicle chassis. The capacit of fuel tank for 1-2.5t is 52L, 60L for 3-3.5t forklift trucks, and the
fuel quantit sensor is fitted on the tank cover of fuel tank to detect the fuel level.
1.4.2 Fuel Quantit Sensor
The fuel quantit sensor is used to convert the remaining fuel quantit in fuel tank into voltage, and refer
to Fig 1-5. The value of resistance will change, when float moves upward and downward, b making use
of allo steel wire to be fabricated into slide resistance connected with float, and the storage fuel quantit
inside fuel tank can be read out from the instrument panel through electromagnetic fuel gauge.
1.4.3 Maintenance of Fuel S stem
The fuel s stem is to be maintained and serviced once for ever work of 100 hours with the following
method, and the fuel tank shall be cleaned once for ever work of 600 hours.
(1) Fuel Filter
Fuel filter is used for remove dust and impurit in fuel, and this fuel filter is located between the fuel tank
and the LPG/Gasoline pump (LPG/Gasoline engine) or oil deliver pump and oil injection pump (diesel
engine).
Service of fuel filter for LPG/Gasoline engine: (including the two items of A) and B))
A) Fuel Filter I for LPG/Gasoline engine is in a through or c lindrical t pe and it shall be replaced
periodicall (namel replacement b ears). (Refer to Fig 1-6). It is peculiar, with one grade of fuel
filtration increased.
B) Fuel filter for LPG/Gasoline engine (Refer to Fig 1-7.)
K Directio
K Directio
Full
Level
Float to Rise to This Place
Resista ce as
Float to Drop
to
This Place
Resista ce as 1
Fuel positio Resista ce as( )
Fig 1-5 Fuel Quantit Sensor
Fig 1-6 LPG/Gasoline Filter
(Speciall Available for LPG/Gasoline Engines)

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a) Take off the oil drain plug (Refer to Fig 1-7) and drain the fuel in gas cup completel .
b) Loosen Nut 1, and detach Filter Core 4.
c) Clean or replace the filter core.
d) After reassembl is completed, start engine for Fuel to be filled into the gas cup of filter. Examine
whether or not gas leak exists, and Parts 8 and 5 seal rings ma be replaced if leak exists.
(2) Service of Diesel Engine fuel filter
This filter is in c lindrical t pe, not detachable generall , and it shall be replaced in complete set if
required.
a) For ever work of 100 hours, dismount the c lindrical shell using special tools, and take out the filter
core.
b) For ever work of 600 hours, the entire filter shall be replaced.
c) It is required to pa attention to examining as to whether or not fuel leak exists after reassembl .
d) Pa attention to examining the working status of Part 1 overflow valve.
Fig 1-7 Fig 1-8
(3)Fuel-Water Separator (Sediment Bowl)
As VE oil injection pump is lubricated with fuel internall , water content in fuel must be separated, and
therefore sediment bowl is used. If indicator light of fuel-water separator turns on, water shall be drained.
(Fig 1-9)
a) Water Drain
Loosen off the fuel drain plug and allow fuel drain plug to drain water manuall . Then tighten the fuel
drain pump and start the pump for multiple times. It shall be ensured that not fuel leak exists, engine is
started, and warning light is turned off. Firml tighten the fuel drain plug

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b) Air Exhaust
Loosen off the air exhaust plug (overflow valve) of oil injection pump, and press the main pump until no
air emits. It shall be ensured that no fuel leak exists.
(4) Cleaning of Fuel Tank
The fuel tank is to be cleaned once for ever work of 600 hours, and attention shall be paid to fire control
for forklift trucks using gasoline engine during cleaning.
Fig 1-9
Ma ual Fuel Pump
Fuel Drai Plug