SsangYong Actyon Sports II. Service manual - part 18

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10. PISTON/CRANKSHAFT/CYLINDER BLOCK

The crankshaft and the cylinder block convert the compression pressure to the rotating energy.

Components

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Cylinder block

Piston

Connecting rod

Crankshaft

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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 bowl type (CR 16.5)

Cooling jet

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(3) Functions

Piston transfers the combustion energy from engine to connecting rod. Especially in the direct injection 

engine such as D20DTR, 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 ring

Locks the piston pin.

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-

-

-

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-

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-

(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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Engine

Piston

Cylinder bore

Part NO

Marking NO.

- 

D20DTR

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