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Closed-roof water jacket (improving coolimg efficiency)
Intake side Exhaust side
Cylinder head oil gallery
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5) Cylinder Head Gasket
The cylinder head gasket is installed between cylinder block and cylinder head to seal the combustion
gas from the combustion chamber, engine oil and coolant.Overview
Location
Cylinder head gasket
3 Layer MLS Gasket
Thickness : 0.7 mm (Compressed)
PFP: Max. 85 bar -
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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. The silent chain provides the
silence during the operation. To improve NVH, the shoulder bolt has been introduced. Overview
Layout and Components
Hydraulic tensioner
Consists of tensioner housing
plug, spring, check valve, and
operated by hydraulic
pressure and spring in
tensioner
Timing chain
Chain type: Silent chain type
Links: 146 ea
Tensioner rail
Installed between exjaust
camshaft sprocket and
crankshaft sprocket
Crankshaft sprocket
Teeth: 21 ea
Oil pump sprocket
Teeth: 28 ea
Exhaust camshaft
sprocket
Teeth:42 eaIntake camshaft
sprocket
CVVT
Teeth: 42 ea
OCV
Controls the hydraulic circuit
to control the intake cam
sprocket variably
Clamping rail
Installed between intake
camshaft sprocket and
crankshaft sprocket
Mechanical tensioner
Operated by spring in
tensioner
Oil pump chain
Chain type: Silent chain type
Links: 58 ea
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1) Timing Gear Case Cover
Features
Major function: Protecting the chain drive system, minor function: Shielding the chain noise
Timing gear case cover prevents the oil from leaking.
The crankshaft front seal and the engine mounting bracket are installed on the timing gear case
cover. -
-
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Timing gear case cover
Do not touch the inner lip of crankshaft front seal installed on the timing gear case cover. -
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Layout and Location
Hydraulic chain tensioner
In G20DF engine, the hydraulic auto tensioner is used to keep the tension for chain drive system of
engine. The auto tensioner is operated by the spring in tensioner and the hydraulic pressure.
2) Hydraulic Auto Tensioner
Oil gallery
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3) Oil Pump Chain Tensioner
Layout and Location
Oil pump chain tensioner
Operated by spring in tensioner
Tensioner type: Compensating and absorbing the impact
Static and dynamic force: spring -
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A. Timing chain
B. Oil pump chain
4) Timing Chain and Gear
Timing chain
Simple layout provides the optimized timing.
Decreased chain vibration and noise
Single stage layout: minimized chain load -
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- Teeth: 146 ea
Teeth: 58 ea
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Components
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.Overview
Layout and Components
Top
Bottom
Oil ring
Piston ring
No.1 ring
Piston pin
No.2 ringSnap ring
Piston