ENGINE SYSTEMS
85
5. Engine Maintenance Standards Table
1. S753 ENGINE (SX21)
* Unit for values without unit in the column of inspection item is mm.
Unit Part Inspection Items
Standard
Dimension
Standard Value
To be
Repaired
Allowable
Limit
Remarks
MAIN MOVING SYSTEM ENGINE
CYLINDER HEAD
Compression pressure of cylinder
MPa (kgf/cm
2
)
More than 2.94
(More than 30)
Less than 2.45
(Less than 25)
Engine 200
rpm
Distortion of face of cylinder head
Less than 0.05
More than
0.12
80
0.85 – 1.15 1.8
Valve sheet
angle 45°
Width of valve seat (intake/exhaust) 1.7 – 2.1 More than 2.5
Tightening torque of cylinder head
N⋅m (kgf⋅m)
49 ~ 52
(5.0 – 5.3)
Coat threads
with
molybdenum
bisulfulde
based grease.
CYLINDER
BLOCK
Bore
75
75 – 75.019
∅75.2
Distortion of upper face of cylinder
block
Less than 0.05 0.12
PISTON
Skirt diameter (longer diameter)
∅75
74.9325 –
74.9475
∅74.7
Clearance to cylinder
0.0525 –
0.0865
0.25
At 20°C
Inside diameter of piston pin hole
∅21
20.998 –
21.002
21.016
Piston pin hole-to-pin clearance -0.004 - +0.004 0.02
PISTON
PIN
Outer diameter of pin
∅21
20.998 –
21.002
∅20.98
Small end bush-to-pin clearance 0.008 – 0.023 0.08 Oil clearance
PISTON RING
Piston ring gap: No.1 ring 0.2 – 0.35
1.0
No.2 ring 0.15 – 0.20
Oil ring 0.15 – 0.35
Piston ring
groove-to-ring
clearance
No.1 ring 0.06 – 0.1
0.25
No.2 ring 0.05 – 0.09
Oil ring 0.02 – 0.06 0.15
Ring width No.1 ring 2 1.97 – 1.99
No.2 ring 1.5 1.47 – 1.49
Oil ring 4 3.97 – 3.99
To Next Page
Loading...
