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02-18
Vacuum pump
Pump capacity: 210 cc/rev
Camshaft speed:
375 to 3,000 rpm
Lubrication temperature:
-40 to 155°C
Oil: 5W30
Drive type: Driven by exhaust
Camshaft sprocket
EGR cooler bypass valve
This valve is controlled by ECU. When the engine
is cooled, the exhaust gas goes to combustion
chamber without passing through EGR cooler
because the valve is closed by vacuum pressure.
2. VACUUM PUMP
Vacuum pump generates the vacuum pressure and supplies it to EGR cooler bypass solenoid. This
pump is single vane type and displacement is 210 cc/rev. The lubrication oil is supplied through the
hole in hollow shaft.
Components ▶
Brake booster and naster
cylinder
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02-24
2) Oil Separator
Oil separator separates the particle in blow-by gas to minimize the engine oil consumption and reduces
the inflow oil from intake system into the combustion chamber. The separated oil returns to oil pan
through cylinder head.
Oil separator
Blow-by outlet hose
(1) Overview
(2) Layout
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02-270000-00
Intake/Exhaust Camshafts
2) Camshaft
(1) Overview
Hollow type camshaft contains cam, octagon cam, HP pump gear and intake/exhaust gears.
Camshaft operates the intake/exhaust valves, vacuum pump and HP pump, and transfers the engine
oil to vacuum pump through the internal oil passage.
(2) Location
Exhaust CamshaftExhaust Camshaft
Thrust journalIntake Camshaft
Closed flow type water jacket (improving cooling performance) ▶
Octagon cam
(for tooling)
Connected to
vacuum pump
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02-30
1) Chain Drive
(1) Overview
The drive chain is single chain drive system with simple design and variable performance, and it utilizes
the hydraulic tensioner to reduce the wave impact generated by the chain. This chain is light weight and
has high durability through single bush chain. Shoulder bolts are used for better NHV.
7. CHAIN AND GEAR DRIVE SYSTEM
D20DTR engine uses single stage chain drive system. Timing chain drives the exhaust side and gear
drive the intake side. Timing chain is single bush type. Upper chain drives HP pump connected to
intake Camshaft by driving exhaust cam shift sprocke, and lower chain drives oil pump to lubricate the
engine.
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02-36
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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02-410000-00
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 ring
Material:
B2+
Skirt coating:
MoS2
Piston cooling gallery
for connecting rod
Wide bawl type (CR 16.5)
Cooling jet
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02-42
(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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02-50
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