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02-40
(3) Functions
Piston transfers the combustion energy from engine to connecting rod. Especially in the direct
injection engine such as D20DTF, it provides the combustion space and largely effects to the
engine performance and exhaust gas.
Piston ring
#1 ring (Top ring) : Prevents the high pressurized combustion gas from leaking into crank
chamber, and prevents the engine oil getting into combustion chamber.
#2 ring: Scrapes the engine oil on the cylinder bore, and prevents the leaked combustion gas
from #1 ring from leaking into the crank chamber.
Oil ring: Scrapes the engine oil on the cylinder bore.
Piston pin
Connects the piston the connecting rod, and transfers the linear movement of piston to
connecting rod to convert it to rotating energy
Snap pin
Locks the piston pin. ▶
-
-
-
▶
-
▶
-
(4) Assembling the piston
Install the piston rings with the "Y" mark on
the ring facing upwards.
Position the end gap of #1 ring at 180˚
away from the end gap of #1 ring.
Position the end gap of oil ring at 180˚
away from the end gap of coil spring, and
position the end gap of oil ring at 90˚ away
from the end gap of #2 ring. 1.
2.
3.
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02-410000-00
EnginePiston Cylinder bore
Part NO Marking NO.-
D20DTF 671 030 06 17 - -
671 037 07 01 A A
671 037 08 01 X X
671 037 09 01 B B
671 037 10 01 +5 -
671 037 11 01 +10 -
Selecting piston oversize
Top of piston Top of cylinder block
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02-46
4) Cylinder Block
(1) Overview
The major dimensions in D20DTR are similar to
D20DT engine. It has two mounting
bosses for knock sensor and meets the
requirements for EURO5 regulation.
(2) Layout
Right sideRight side
Expansion plug
Screw plug
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02-48
The bottom side of water jacket is desgined as sine wave to strengthen the structure of crankcase.
The main flow of coolant starts from outlet port of water pump and goes along the longitudinal
direction of engine. The coolant passage from cylinder head to inlet port of water pump is
integrated in cylinder head.
The engine oil from oil pump is supplied to the main oil gallery through oil channel, oil filter
module and cross bore in cylinder block without using external pipes. This oil is supplied to main
bearing, cylinder head and MBU. And, it is sprayed to the chain through the chain tensioner
connected to cross bore.
Crankcase cross bore for oil supply
Water jacket core
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03-32210-01
1. SPECIFICATION
Description Specification
Fuel Diesel
Fuel filterType Fuel heater + priming pump + water
separator integrated type
Filter type Changeable filter element type
Change interval every 50,000 km
Water separation interval every 15,000 km
Water accumulating capacity 200 cc
Heater capacity 250W 13.5V
Injector System pressure 1800 bar
High pressure fuel
pumpType Eccentric cam/Plunger type
Operating type Gear driven type
Normal operating temperature-40 ~ 125˚C
Operating pressure 1800 bar
Operating temperature-30 ~ 120˚C
Low pressure fuel
pumpType Vane type
Gear ratio (pump/engine) 0.5 : 1
Pressure 6 bar
Fuel tankCapacity 75 L
Material Steel
Fuel sender Single sender type
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03-4
2. MAINTENANCE AND INSPECTION
1) Maintenance Procedures for DI Engine Fuel System
Always keep the workshop and lift clean (especially, from dust).
Always keep the tools clean (from oil or foreign materials).
Wear a clean vinyl apron to prevent the fuzz, dust and foreign materials from getting into fuel
system. Wash your hands and do not wear working gloves. 1.
2.
3.
Follow the below procedures before starting service works for fuel system.
If the problem is from HP pump, fuel supply line or injector, prepare the clean special tools and
sealing caps to perform the diagnosis for DI engine fuel system in this manual. At this point,
thoroughly clean the related area in engine compartment. 4.
Clean the engine compartment before starting service works.
Tool kit for high pressure lineTook kit for low pressure line
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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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03-6
2) Diagnostic Test for Engine Fuel System
(1) Overview
If a DTC is displayed on the diagnostic device, check the low pressure- and high pressure fuel
systems before removing the components.
To run the system properly, the electric system must be intact but for the DI engine, the fuel
pressure should be measured also when there is a malfunction even after the diagnostic test with
a diagnostic device.
(2) Hydraulic system