Kubota G2160, Workshop Manual

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P1-S17
G2460G, WSM ENGINE
[2] ENGINE BODY
(1) Checking and Adjusting
Compression Pressure
1. After warming up the engine, stop it and remove the air cleaner,
the muffler and all spark plugs.
2. Install a compression tester (Code No: 07909-30251) for
gasoline engines to spark plug hole.
3. Run the engine at 7.5 S
-1
(450 rpm) with the starter for 5 to 10
seconds keeping throttle valve fully open.
4. Read the maximum pressure. Measure the pressure more than
twice.
5. If the measurement is below the allowable limit, apply a small
amount of oil to the cylinder wall through the spark plug holes and
measure the compression pressure again.
6. If the compression pressure is still less than the allowable limit,
check the top clearance, valve and cylinder head.
7. If the pressure increases after applying oil, check the cylinder
wall and piston rings.
NOTE
■
• Check the compression pressure with the specified valve
clearance.
• Always use a fully charged battery for performing this test.
• Variances in cylinder compression values should be under
10 %
.
W1022479
Top Clearance
1. Remove the cylinder head and the head gasket completely.
2. Bring the piston to it TDC, and fasten 1.5 mm dia. 5 to 7 mm long
fuse wires to 3 to 4 spots on the piston top with grease so as to
avoid the intake and exhaust valve and the combustion chamber
ports.
3. Bring the piston to its middle position, install the cylinder head,
and tighten the cylinder head bolts to specification.
(Head gasket must be changed to new one.)
4. Turn the flywheel until the piston passes through the TDC.
5. Remove the cylinder head, and measure the thickness of the
fuses.
6. If the measurement is not within the factory specifications, check
the oil clearance between the crankpin and bearing and between
the piston pin and bushing.
NOTE
■
• After checking the top clearance, be sure to assemble the
cylinder head with a new cylinder head gasket.
W10107680
Compression pressure
Factory spec.
1.27 MPa
13.0 kgf/cm
2
185 psi
Allowable limit
0.88 MPa
9.0 kgf/cm
2
128 psi
Top clearance
(Engine serial No.: above 1A0001)
Factory spec.
0.85 to 1.30 mm
0.0335 to 0.0512 in.
Top clearance
(Engine serial No.: below YY8644) 1.45 to 1.75 mm
0.057 to 0.0690 in.
Tightening torque Cylinder head bolt
37.2 to 42.1 N·m
3.8 to 4.3 kgf·m
28.0 to 31.7 ft-lbs
KiSC issued 11, 2006 A