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01-8
4. CAUTION WHEN SERVICING THE ENGINE
1) Cleaness
Engine has a lot of precisely machined (grinding, polishing, lapping) surfaces. Thus, there should be great
cautions for cleaness when servicing the engine components. Apply the engine oil on the sliding surfaces
when assemblying the components. Every component should be disassembled and reassembled in
accordance with the correct sequences. Before servicing the engine, the negative cable should be
diconnected from the battery. Otherwise, some electric or electronic components could be damaged.
2) Servicing
(1) Lifting up the vehicle
Always keep the safety precautions.
To prevent the vehicle from rolling down, put the chocks under the tires (when using a 4-post lift).
Make sure to support the correct lifting points (when using a 2-post lift) -
-
-
(2) Exhaust system
Wear the safety glove when removing the exhaust pipe.
Make sure that the exhaust pipe is cooled before removing it. -
-Before service work, be sure to disconnect battery negative (-) terminal to prevent damages by bad
wire and short.
To prevent the foreign material from getting into engine cylinder, cover the inlet of air cleaner if the
air cleaner has been removed -
-
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02-110000-00
4. GUIDELINES ON ENGINE SERVICE
To prevent personal injuries and vehicle damages that can be caused by mistakes during engine and
unit inspection/repair and to secure optimum engine performance and safety after service works, basic
cautions and service work guidelines that can be easily forgotten during engine service works are
described in.
Cautions before service works
For safe and correct works, you must observe the working procedures and instructions in this
manual. And, use the designated tools as follow:
Engine stand / Heavy duty engine jack
To prevent the engine from starting abruptly, do not allow anybody to get in the vehicle while
servicing in engine compartment.
Before work on engine and each electrical equipment, be sure to disconnect battery negative (-)
terminal.
Before service works, be sure to prepare the works by cleaning and aligning work areas.
Do not allow the foreign material get into the fuel injection system.
When removing the engine, use only the safety hook on engine and engine hanger. Do not support
the bottom of oil pan with a jack.
Engine and accessories ▶
-
-
-
-
-
-
▶
Completely drain the engine oil, coolant and fuel from engine before removal.
Before disassembling/assembling the engine components, carefully read the working procedures in
this manual.
Make sure to keep the specified tightening torques during installation.
Clean and properly lubricate the parts before reassembly.
Carefully check that there are not any interference while servicing. -
-
-
-
-
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02-30
2) Timing Chain and Gear
(1) Timing chain
Simple layout: optimized timing, enhanced
NVH
Single stage layout: minimized chain load -
-
Chain upper bush
- Single bush type (112 EA)
Chain lower bush
- Single bush type (60 EA)
(2) Tensioner
Tensioner adjusts the chain tension to keep it tight during engine running. This reduces the wear in
guide rail and spoke.
Operating principle
- Use the spring tension in tensioner and hydraulic pressure
Tensioner type
- Compensation and impact absorbing
Static and dynamic force
- Spring + Hydraulic pressure 1.
2.
3.
Plunger
HousingSpring
Check valve
Hydraulic tensioner assembly ▶
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02-34
Oil pan sassembly
8. OIL PAN
The oil pan in D20DTR engine improves the NVH. Especially, the oil draining is much easier than before.
Components ▶
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02-390000-00
1) Piston
(1) Overview
Piston assembly contains piston, #1 ring, #2
ring, oil ring, piston pin and snap ring. The
expansion energy from engine is transferred to
the crankshaft through connecting rod to convert
the linear movement to rotating energy.
(2) Layout
#1 ring
Oil ring
Snap ring
#2 ringMaterial: B2+
Skirt coating:
MoS2
Piston cooling gallery for
connecting rod
Wide bowl type (CR 16.5)
Cooling jet
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03-52210-01
Follow the job procedures. If you find a defective component, replace it with new one. 5.
Once disconnected, the fuel pipes between HP pump and fuel rail and between fuel rail and each
injector should be replaced with new ones. The pipes should be tightened tospecified tightening torques
during installation. Over or under torques out of specified range may cause damages and leaks at
connections. Once installed, the pipes have been deformed according to the force during installation,
therefore they are not reusable. The copper washer on injector should be replaced with new one. The
injector holder bolt should be tightened to specified tightening torque as well. If not, the injection point
may be deviated from correct position, and it may cause engine disorder.
Plug the removed components with clean and undamaged sealing caps and store it into the box to
keep the conditions when it was installed. 6.
To supply the fuel to transfer line of HP pump
press the priming pump until it becomes
hard. 7.
Priming pump
Priming pump cap
Fuel filter assembly
Check the installed components again and connect the negative battery cable. Start the engine and
check the operating status.
With Scan Tool, check if there are current faults and erase the history faults. 8.
9.
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03-20
(2) Di engine and its expected problems and remedies can be caused by
water in fuel
System supplement against paraffin separation ▶
In case of Diesel fuel, paraffin, one of the elements, can be separated from fuel during winter and then
can stick on the fuel filter blocking fuel flow and causing difficult starting finally. Oil companies supply
summer fuel and winter fuel by differentiating mixing ratio of kerosene and other elements by region and
season. However, above phenomenon can be happened if stations have poor facilities or sell improper
fuel for the season. In case of DI engine, purity of fuel is very important factor to keep internal
preciseness of HP pump and injector.
Accordingly, more dense mesh than conventional fuel filter is used. To prevent fuel filter internal clogging
due to paraffin separation, SYMC is using fuel line that high pressure and temperature fuel injected by
injector returns through fuel filter to have an effect of built-in heater (see fuel system).
System supplement and remedy against water in fuel ▶
As mentioned above, some gas stations supply fuel with excessive than specified water. In the
conventional IDI engine, excessive water in the fuel only causes dropping engine power or engine
hunting. However, fuel system in the DI engine consists of precise components so water in the fuel can
cause malfunctions of HP pump due to poor lubrication of pump caused by poor coating film during high
speed pumping and bacterization (under long period parking). To prevent problems can be caused by
excessive water in fuel, water separator is installed inside of fuel filter. When fuel is passing filter, water
that has relatively bigger specific gravity is accumulated on the bottom of the filter.
Water drain from water separator ▶
If water in the separator on the fuel filter exceeds a certain level, it will be supplied to HP pump with fuel,
so the engine ECU turns on warning lamp on the meter cluster and buzzer if water level is higher than a
certain level.
Due to engine layout, a customer cannot easily drain water from fuel filter directly, so if a customer
checks in to change engine oil, be sure to perform water drain from fuel filter.
Water
separator
To separate the water from the fuel filter,
remove the fuel filter assembly first.
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03-232210-01
Accelerator pedal position
sensor
Detecting driver's intention
for speed up/down
Fuel rail assembly
Relieving the pulsation.
Measuring the fuel pressure.
Distributing the fuel to injectors.
Fuel filter assembly
Supplying clean fuel/fuel
heating/water separation by
priming pump
Plunger type HP pump (1,800 bar)
Vane type LP pump (6 bar)
T-MAP sensor
Measuring booster pressure
and temperature
High pressure pump
Generating high pressurized fuel and
supplying it according to engine rpm,
required volume, required pressure