Deutz WP6C Series User manual

Deutz WP6C/WP4C Series Marine Diesel Engines
Operation and Maintenance Manual and
User Service Guide
13060345

Deutz WP6C/WP4C Series Marine Diesel Engine Operation and Maintenance Manual
Deutz WP6C/WP4C Series Marine Diesel Engine User Service Guide
Important
In order to ensure your safety and give full play of high performance of diesel engine, please
carefully read this manual before operating the diesel engine and closely abide by the
operation and maintenance procedures specified in this manual.
In order to protect your lawful rights and interests, never dismantle the lead sealing for the
fuel amount from the fuel pump without permission.
The guarantee from the factory will be invalid for adjusting the fuel injection pump or
dismantling the lead sealing.
Because the fuel injection pump is sophisticated component, users are not allowed to
dismantle it. Failure to do so will cause the factory's guarantee invalid.
Because the rotor shaft of supercharger is sophisticated high-speed rotating part, users are not
allowed to dismantle it or let it be impacted. Failure to do so will cause the factory’s
guarantee invalid.
Because of the strict torque and turn angle requirements for the main bearing bolts and
connecting rod bolts of diesel engine, users are not allowed to loosen and dismantle them.
Failure to do so will cause the factory’s guarantee invalid.
At any time of starting the diesel engine, please check whether the coolant and oil is fully
filled.
As the connecting rod bolts are disposable, never reuse them.

Deutz WP6C/WP4C Series Marine Diesel Engine Use and Maintenance Manual
Deutz WP6C/WP4C Series Marine Diesel Engine User Service Guide
Precautions
1. Before delivery of the engine, the delivery test is already and strictly done based on test
specifications. As the throttle openness is already limited by lead sealing, never randomly
dismantle the lead sealing to increase the throttle. Otherwise, our factory will not perform the
Three-guarantee. Users are hoped to pay attention to this.
2. The operator should carefully read this Operation and Maintenance Manual, be familiar with
the structure of this diesel engine and closely abide by the technical operation and
maintenance procedures specified in this manual.
3. Before using the new diesel engine, please perform the trial operation for 50h.
4. After the diesel engine is cold started, please slowly increase the rotating speed and never
idle for long time. After engine running with load, do not immediately stop it. It is necessary
to idle for 5-10 min at low speed.
5. After engine is stopped, if the ambient temperature is lower than 0 , yet the antifreeze℃
additive is not applied, please completely drain the water in water tank and diesel engine.
6. The diesel engine is prohibited to work without air cleaner which could prevent unfiltered air
from entering the cylinders.
7. Please select the specified fuel and oil grades which will be filled into the diesel engine (it is
suggested to use Weichai Power special oil sold at all service stations of Weichai). Use the
special clean container. The fuel and oil should be filtered through the strainer before being
added. Precipitate the fuel for 72h or more.
8. The inspection of electrical system should be done by the personnel mastering the electrical
knowledge.
9. The valid duration of oil sealing for the diesel engine is one year. If the valid duration is
beyond one year, please take necessary supplement measures.
10. The power calibration and revision of diesel engine should be based on the
CB/T3254.1-1994.

Deutz WP6C/WP4C Series Marine Diesel Engine Operation and Maintenance Manual
Deutz WP6C/WP4C Series Marine Diesel Engine User Service Guide
Preface
WP6/WP4 series marine diesel engines are manufactured by Weifang Weichai Deutz Diesel
Engine Co. Ltd - the joint venture of Weichai Power Co. Ltd and Deutz AG. This series diesel
engines are classified into supercharge type and supercharge and intercooled type based on the
aspiration methods. There are two kinds of cylinder types: 4-cylinder and 6-cylinder. These series
diesel engines are of four stroke, water cooling, in-line, DI combustion chamber and high speed
engines, featuring by compact structure, reliability operation, excellent power performance and
economy indexes, advanced emission indicators, quick start, easy operation and convenient
maintenance etc. These series diesel engines are the ideal propulsion power for small vessels used
for inland water transportation, fishery and high-speed ships.
This manual mainly covers the main technical parameters, performance indicators, structural
features and operation and maintenance precautions for WP6/WP4 series marine main and
auxiliary engines. Before using this engine, please closely follow all requirements specified in this
manual. This could ensure the operation reliability and prolong the useful life of diesel engine.
Before servicing, disassembling and installing the diesel engine, please carefully read the Deutz
WP6/WP4 Series Marine Diesel Engine Parts Catalogue to master the basic structures of all
systems of the diesel engine.
What this manual describes is the basic models of WP6/WP4 series marine diesel engines. As to
other model information which is not listed into basic model, users could consult according to the
contact phone, fax etc on the “User Feedback Card”. As the products continuously develop, the
structure will also change. Partial content in this manual may be slightly different from the actual
products. This manual will be subject to be revised without notice. Access the www.weichai.com
for updated product information and hope users timely pay close attention to all the issued
technical information. If you feel the content important, please timely contact with the technical
department or sale department of Weichai Power Co. Ltd to avoid unnecessary trouble during the
normal use and maintenance.
Welcome comments and suggestions for product improvement from users. Please send the “User
Feedback Card” annexed at the end of this manual to the Sales Company or Application
Engineering Department of Weichai Power Co. Ltd.
Mar.2010

Deutz WP6C/WP4C Series Marine Diesel Engine Use and Maintenance Manual
Deutz WP6C/WP4C Series Marine Diesel Engine User Service Guide
Contents
I. Deutz WP6C/WP4C Series Marine Diesel Engine Use and Maintenance
Manual


WP6/WP4 series diesel engines model meaning ...........................................................................1
WP6/WP4 series marine diesel engine structural features:............................................................1
1 Main performance and technical parameters for WP6C/WP4C series marine diesel engines
..........................................................................................................................................................2
2 Fuel, oil and coolant used for diesel engines..............................................................................3
2.1 Oil ...............................................................................................................................................3
2.2 Fuel .............................................................................................................................................3
2.3 Coolant........................................................................................................................................4
3 Diesel engine installation and connection...................................................................................6
3.1 Diesel engine hoisting.................................................................................................................6
3.2 Diesel engine installation............................................................................................................6
3.3 Installation of external connection systems for diesel engine.....................................................7
4 Operation and maintenance of diesel engine.............................................................................8
4.1 Preparations before operation .....................................................................................................8
4.2 Operation precautions...............................................................................................................10
4.3 Maintenance of diesel engine....................................................................................................11
5. Common fault analysis and troubleshooting..........................................................................13
II. User Service Guide (Warranty Card)...................................................................1
Weichai Power Product Warranty Card (for User)............................................................................1
Maintenance Registration Form (Filled by Maintenance Personnel)................................................2
Warranty Instructions........................................................................................................................3
Regulations about Term of Three Guarantees Service for Weichai Power Marine or Power
Generating Diesel Engine .................................................................................................................5
Customer Satisfaction Questionnaire................................................................................................6
Engine Mandatory Maintenance Card

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WP6/WP4 series diesel engines model meaning
The symbols of all models from the WP6/WP4 series diesel engines are shown as follows:
Table 1
Rotating speed 1500r/min
1800r/min
2100r/min
2300r/min
2500r/min
Rotating speed code 15 18 21 23 25
WP6/WP4 series marine diesel engine structural features:
One head for one cylinder, reliable operation and convenient disassembly.
With the high body rigid, preassembled camshaft sleeve should increase the engine reliability.
Compact engine layout, special and flat oil sump, convenient for matching with the ship.
Rotating speed code (see table 1)
Dash
Power code (expressed in HP)
Application feature symbol (C- marine main engine; CD
-
marine auxiliary engine)
Total displacement L
Weichai Power

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Tab le 1
1 Main performa nce and technical parameter s for WP6C/W P4C series marine diesel engines

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2 Fuel, oil and coolant used for diesel engines
2.1 Oil
Quality grade: Oil should be classed according to its quality and features. Generally apply the
API or GB for classification.
Oil allowable to be used: CD grade or better
Viscosity
Oil viscosity greatly depends on the temperature. Please refer to the fig.2-1 (ambient
temperature ) to select proper oil.℃The ambient temperature should not exceed the temperature
limit for long time to keep the wear within the lowest limit.
Ambient
temperature.
Multi-grade oil Single-grade oil
Fig.2-1 Selection of oil grade
Suggestion:
1. Use the multi-grade oil to avoid changing oil as the season changes. Therefore the fuel
consumption rate can be decreased.
2. If the ambient temperature is -15℃or more, use the CF-4 grade 15W/40 oil. If the ambient
temperature is -15℃or less, use the 5W/20 oil.
It is recommended to use the Weichai Power special (Shell) 15W-40 oil, which is mixed by the
imported quality basic oil and selected additive. This oil is sold at all service stations of Weichai at
the unified national sale price.
Caution:
1. Do not check the lubricant level during engine running.
2. It is not allowed to mix the different grades of oil.
2.2 Fuel
This diesel engine uses the light diesel as the fuel;
Quality grade
Sulfur content in the fuel of specified grade should not be higher than 0.5%.
Apply the following grades of diesel fuel based on the ambient temperature.

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If the ambient temperature is higher than 5℃, it is recommended to use the 0# diesel (GB 252-94)
At low temperature, the diesel fuel may precipitate the waxy material which causing poor
flowability of diesel fuel. In such case, the fuel system will be clogged, causing failures of diesel
engine. Therefore when the ambient temperature is less than 0 , please use the winter diesel℃fuel.
According to the GB252 diesel fuel standard, if the ambient temperature is -5 or more, please℃
choose the -10# diesel fuel. If the ambient temperature is -14 or more,℃please choose the -20#
diesel fuel. If the ambient temperature is -29 or more, please choose the℃-35# diesel fuel. If the
ambient temperature is -44 or more, please choose the℃-50# diesel fuel.
2.3 Coolant
The coolant of diesel engine should be soft water added by the anticorrosive agent and
long-lasting antifreeze.
Long-lasting antifreeze
Long-lasting antifreeze is of resistance to corrosion and freeze. Please refer to antifreeze related
manual for the proportion of long-lasting antifreeze. See the table 2-1 for the domestic long-lasting
antifreeze.
Table 2-1 Domestic long-lasting antifreeze
Grade
Items JFL-318 JFL-336 JFL-345
Glycol content % 33 50 56
Specific gravity (15.6 )℃1.05 1.074 1.082
Boiling point ℃104.5±1 108.5±1 110.0±1
Freezing point ℃-18±1 -36±1 -45±1
Proper min. temperature ℃-10 -26 -35
Caution
1. Periodically check the antifreeze concentration if temperature is below 0 .The℃
℃℃
℃
concentration of antifreeze should be inspected every 1000h yet at least once for
each quarter. The antifreeze should be changed every two years to avoid
corrosion.
2. As to the regions where the temperature is always higher than 0℃
℃℃
℃, use the
water anti-rust and anti-scale treated as the coolant. Never use the untreated
water as the coolant.
Anti-corrosive agent
If the ambient temperature is higher than 5℃(in summer or autumn or regions with higher
temperature), the anti-corrosive agent should be added into the coolant (NL emulsified anti-rust
agent or LQS comprehensive protective agent). Please refer to related manual for the proportion of
anti-corrosion agent and soft water.
Coolant
For the composition of coolant, see the table 2-2.

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Table 2-2 Coolant composition
Water quality min
max
PH 6.5
8.5
Only if the coolant meets the water-quality
composition, can it be mixed with the
antifreeze or anti-corrosion agent.
Chloride ion content mg/dm
3
- 100
Carbonate content mg/dm
3
- 100
Total negative ion content mg/dm
3
- 150
Total hardness when using the
long-lasting antifreeze, mg/dm
3
3 12
Carbonate hardness mg/dm
3
3 -
Total hardness when using the
anti-corrosive agent (take note of the
instruction of supplier) mg／dm
3
0 10
Note: Because inner galvanized tube is not suitable to use anti-corrosive agent, this tube is not
used as the coolant pipe.

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3 Diesel engine installation and connection
3.1 Diesel engine hoisting
Incorrect hoisting will cause damage to diesel engine.
Fig. A
Fig. B
2 special cylinder-head bolts have been installed on each diesel engine, which are used for hoisting
diesel engine. AM14 threaded rod is mounted on the six-square end face of the two bolts, which is
used to mount the special slings (see fig. A) and lifting eyes. When using the special slings, screw
the suspender with M14 threaded hole onto two cylinder head bolts, adjust the center of gravity
and then it is good for hoisting. If the engine is hoisted through the lifting eyes attaching to the
cylinder head bolts, the slings as shown in fig. B is recommended. When hoisting the engine, its
crankshaft should be at horizontal level and two slings should at parallel status. Do not use one
sling which will lift the engine in the way of triangle. If you use one sling, the sling, cylinder head
bolts and lifting eyes are not at the same line. Therefore, this could cause damage to the bolts and
even fracture during hoisting, leading to damage to diesel engine.
3.2 Diesel engine installation
Apply the elastic coupler and ensure the crankshaft center line is concentric to the axis of the input
shaft of gearing equipments (gearbox, transmission). There should be no additive axial force on
the crankshaft caused by installation.
Correct
Wrong

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3.3 Installation of external connection systems for diesel engine
The exhaust pipeline of diesel engine should avoid excessive bends. Expansion joint should be
mounted around the middle of the pipeline. In addition, additive support should be mounted for
pipeline. The inner diameter of exhaust pipeline should not be less than 83mm and the exhaust
back pressure should not be less than 6kPa.
Rain cover should be mounted onto the outdoor outlet of exhaust pipe. In order to smoothly drain
the condensed water from the exhaust pipe, water drain valve should be installed at the lowest
place of the exhaust pipe.
Waterproof cap should be installed onto the outdoor inlet to prevent the rain water from entering
the intake system.
The capacity of fuel tank should satisfy that the diesel engine works for 8h at rated load. The fuel
tank should be positioned where the fuel filler is not lower than inlet of fuel delivery pump. The
inner diameter of fuel pipeline should not be less than 12mm.

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4 Operation and maintenance of diesel engine
4.1 Preparations before operation
4.1.1 Unseal
When the diesel engine package is opened, first, the user should check the diesel engine and
accessories according to the factory packing list, check whether the diesel engine surface is
damaged, whether the connecting pieces are not loosened, etc., and then carries out the following
operations:
(1) Scrub the rustproof layer, the anticorrosive agent, etc. of the exposed parts.
(2) Drain the oil-sealed oil of the fuel filter and the fuel system parts (starting without draining
the oil-sealed oil of the fuel system is permitted, but only when the oil-sealed oil of the fuel
system is consumed and the normal diesel fuel is available, the loaded operation of engine is
permitted.)
(3) Check whether the water plug and the oil plug are plugged, whether the water temperature
and oil temperature sensors are complete, and make sure that all necessary parts are available.
Note: Do not start before the diesel engine is correctly installed and connected to the final
position. Ensure the ventilation and make sure that the exhaust gas is emitted to the
atmosphere when the diesel engine runs in enclosed environment.
4.1.2Add the oil
(1) The oil should meet the specified requirements; otherwise, it may lead to insufficient oil
pressure, even wear and starting difficulty. The oil must be very clean. Weichai Power special
oil (Shell) CD/15W-40 is recommended (refer to 2.1).
(2) Tighten the oil drain plug.
(3) Open the oil filler cap (refer to figure 4-1) and add the oil through the filter screen.
(4). Place the diesel engine on the flat ground, and pull out the dipstick to check the oil level. Add
oil to the upper limit of the dipstick when necessary.
(5) Tighten the oil filler cap. Note: Check the oil level every time before starting the diesel
engine.
Figure 4-1 Engine oil filler

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4.1.3Add the fuel
(1) The diesel fuel should meet the related regulations (refer to 2.2).
(2) Pay attention to the cleanliness of the diesel fuel, and store the diesel fuel still for above 72h
before adding.Add the diesel fuel into the fuel tank through the internal filter screen.
Note: Check the diesel fuel level every time before starting the diesel engine.
4.1.4Air bleeding of fuel system (Refer to figure 4-2)
(1) Unscrew the fuel screw 1 at the outlet of fuel delivery
pump for half a turn. Operate the hand pump 2 of the fuel
delivery pump 3 until the diesel fuel emits out and then
tighten the fuel screw.
(2) Unscrew the air bleed screw 4 on the fuel filter 5. Operate
the hand pump of the fuel delivery pump until the diesel
fuel emits out and then tighten the air bleed screw.
(3) Unscrew the air bleed screw 6 on the fuel injection pump
7. Operate the hand pump of the fuel delivery pump until
the diesel fuel emits out and then tighten the air bleed
screw.
(4) Continue to operate the hand pump, check the fuel line for leakage, and then tighten the hand
pump.
4.1.5Add the coolant
The coolant is prepared from softened cleaning water and anticorrosion agent or antifreeze, strictly
conform to the regulations of additive manufacturer during preparation (refer to 2.3).
Add the coolant from the water filler of the radiator or the heat exchanger, and bleed the air from
the cooling circulation system.
Note: Frequent water adding and changing will generate scales in the system. Repair the
leakages of the cooling system as soon as possible. Add softened cleaning water as much as
possible and try to avoid frequent changing of coolant. The coolant drained from the water
tank can be reused after being filtered by fabric and fine screen.
Check the coolant level every time before starting the diesel engine.
4.1.6 Battery charging
Please refer to the battery instruction manual.
Note: The gases generated during charging are explosive. No smoking is allowed around the
battery, and the battery must be kept away from any naked flame and spark. There is strong
corrosive acid in the battery, please flush with a large amount of fresh water if the acid is
splashed into the eyes or on the skin.
Operation sequence for charging:
(1) Open the seal cover.
(2) Add the battery sulfuric acid from the filler to the marked position.
(3) Fasten the seal cap.
(4) Apply antirust grease on the battery electrodes.
(5) Connect the terminal and the electrodes, Connect the positive electrode firstly.
Figure 4-2 Air bleeding of fuel system

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(6) It is not allowed to place any metal object on the battery.
(7) Check the sulfuric acid level every day after the use of battery. Add distilled water if needed.
4.2 Operation precautions
4.2.1 Operation precautions
Prior to starting the diesel engine, check the levels of oil, cooling water and fuel and the
connections of pipelines (refer to 4.1).Rotate the crankshaft for several turns and confirm that
there is no clamping or binding phenomenon.
When starting the diesel engine, if it is not started in 15s, wait for 2min and then restart it.
After starting the diesel engine, run it at idle speed for 2~3min and the oil pressure should be
higher than 120kPa, if not, stop it immediately for check; if the cooling water temperature is not
higher than 60 , do not run the diesel engine suddenly in high speed and with large load, because℃
this will affect the wear resistance and the reliability of the engine.
Check the diesel engine for “three leakages” every time after operation.
If the diesel engine runs with load, prior to shutdown, decrease the load, lower the speed, and run
it at idle speed for 4-5min to avoid full-load shutdown;
Check the oil level of the diesel engine: carry out the check 5min later after shutdown.
Note: To avoid damaging the diesel engine, during operation, it is not allowed to remove the
cable connecting the diesel engine pressure regulator and the cable connecting the battery
anode. Different from the DC generator, it is not allowed to check the alternator voltage by
grounding temporarily.
4.2.2 Precautions for starting and operation in cold environment
(1) If long-acting antifreeze is not added in the cooling water of the diesel engine, during use in
cold days, the cooling water must be drained out after shutdown to avoid frosting the diesel
engine. Open the special drain valve (Refer to figure 4-3) at lower position of the cylinder
block of injection pump side, the cooling water in the diesel engine can be drained out.
Figure 4-3 Drain valve
(2) Before the cold seasons begin, check electrolyte level, viscosity and unit voltage of the
battery. If the engine is in an environment with very low temperature for a long time, take the
battery down and store it in a warm room.

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4.3 Maintenance of diesel engine
Maintenance schedule of diesel engine
No repetitive operation is needed after maintenance according to the following time:
Operation item Running time h
Retighten the connecting bolts and the cylinder
head bolts 30
Check the belt and the tightness 30 125
Change the oil and replace the oil filter
element 30 125
Check the valve clearance 30 125
Repeat the maintenance operation according to the following time:
Operation item Running time h
250 500 1000
Clean the air filter element
1)
×
Check and tighten the V-belt ×
Check the raw water pump impeller
2)
×
Check the zinc anode
2)
×
Change the oil and replace the oil filter element
×
Check the valve clearance ×
Replace the diesel filter element ×
Clean the crankcase ventilation device
3)
×
1). Replace earlier if there is more dust.
Clean the wet air filter at least in 200h’s operation.
2). Only for marine engines only.
3). Only for conditions when the crankcase ventilation device is not guided to air inlet
Maintenance instructions for standby state and emergency state
Seal the diesel engine up if it is not used for weeks (for example, in winter).
Time Maintenance requirements
Every month Trial run with load
6 months After operating for 6 months, if the operation time does not reach 500h, carry
out all maintenance operations required in this period.
After12 months
After operating for 12 months, if the operation time does not reach 1000h,
carry out all maintenance operations required in this period.

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Overhaul
The operation reliability of the diesel engine will be affected by wear and corrosion. To avoid
abnormal operation of the diesel engine, we recommend that complete overhaul be carried out
according to the following table. Carry out the first overhaul after 2000h’s or 2 years’ (in the case
of not reaching to 2000h) operation of the diesel engine.
Items Operation time
Check the nozzle 2000
Check the compression pressure 2000
Check the bearing clearance of water pump 5000
Check the supercharger 5000
Check the fuel injection pump 5000
Check the cylinder head 5000
Check the cylinder liner 5000
Clean the water cavity of the water cooling
exhaust pipe and check the corrosion 10000
Check the connecting rod and the main bearing
10000
Check the piston 10000
Check the crankshaft 10000
Check the camshaft 10000
Check the secondary balance mechanism 10000
Check the transmission gear 10000
Overhaul the fuel injection pump thoroughly 10000
Replace the oil pump 10000
Replace the water pump 10000
Replace the crankshaft oil seal 10000
Replace the shock absorber 10000
The above checks and repairs require professional skills and should be carried out by
professionals.

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5. Common fault analysis and troubleshooting
5.1 The diesel engine cannot start
S/N
Cause Troubleshooting
1 Use
(1) Air starter: The air pressure
in the starting air bottle is
insufficient or is not in
optimal starting position.
Always keep the pressure in the air bottle above
2MPa; prior to starting, barring the engine and make
one of the cylinders at an angle about 15° behind the
top dead center.
(2) Electric starter: The battery is
low in capacity.
Check the specific gravity of battery electrolyte
(which should be 1.28-1.30) and keep the battery
warm in winter or cold regions or use the insulation
(low-temperature) battery.
(3) The service handle is not in
the service position. Tighten the service handle to the service position.
(4) The diesel engine is loaded. Unloading
(5) The oil viscosity is high and
the liquidity is poor. Select the oil according to ambient temperature or heat the oil.
(6) There is air in the fuel
system. Bleed the air in the system.
(7) There is water in the diesel
fuel. Check the fuel tank; unscrew the plug at the lower part of the diesel filter, and discharge the water.
(8) The bleed screw of the fuel
injector is not tightened, and
there is no fuel injection. Tighten it clockwise.
(9) The selected diesel fuel is
improper. Select according to regions and seasons.
2 Fuel system
(1) There is leakage from the
fuel pipe joint. Check and tighten the joint.
(2) The fuel pipe is blocked. Check and clean or blow free the fuel pipe.
(3) The diesel filter is blocked. Remove, clean or replace the filter element.
(4) The spray of the fuel injector
is not good. Adjust and repair the fuel injector. Replace the needle valve coupled parts when necessary.
(5) The fuel supply advance
angle is incorrect. Adjust as required.
(6) The fuel injection pump or
the fuel injector is damaged. Overhaul or replace
3 Others
(1) There is leakage from the
inlet/exhaust valve. Overhaul and readjust the valve clearance.

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S/N
Cause Troubleshooting
(2) There is air leakage from the
cylinder. Check the cylinder head gaskets and tighten the cylinder head nuts.
(3) The valve spring is broken. Replace it.
(4) There is gas leakage from the
piston rings. Replace the piston ring.
(5) The piston is stuck in the
cylinder. Remove and repair.
(6) There is gathered water in
the cylinder. Remove the cylinder head, drain the water, and find out the cause.
(7) The timing of air distribution
plate of the air starter is
wrong. Remove and reinstall.
5.2 The diesel engine cannot output specified power
S/N
Cause Troubleshooting
1 Use
(1) The speed is low. Adjust to the rated speed.
(2) The elevation or ambient temperature of
operation regions is too high.
Correct according to the
environmental conditions, refer to
annex “Power correction table”.
2 Fuel system
(1) The fuel injector is faulted (the injection hole
is clogged, the spray is not good, the fuel
injection pressure is insufficient, or the height
of the injection nozzle stretching out of the
cylinder head is incorrect).
Adjust or overhaul the fuel injector as
required.
(2) The fuel supply of the fuel injection pump is
uneven or one or two sub-pumps are
inoperative.
Adjust the fuel capacity or overhaul
the fuel injection pump.
(3) The fuel injection pump is worn, the fuel
supply is insufficient.
Unscrew the limit screw of the fuel
pump control rack, increase the fuel
capacity or replace a new plunger and
barrel assembly.
(4) The diesel fuel filter is clogged, the fuel
pressure of the fuel delivery pump is
insufficient, the check valve of the fuel
delivery pump is broken or worn, or the
spring is broken.
Check and clean or adjust and replace
(5) The diesel fuel selected is improper. Select the specified grade according to regions and seasons (ambient
temperature).
(6) The fuel supply advance angle is incorrect. Check and adjust
3 Air distribution system