Mitsubishi S3Q2, Руководство по обслуживанию

Страница: 47 / 176

DETERMINATION OF OVERHAUL
4-3
2. Testing compression pressure
&$87,21
(a) Be sure to measure the compression pressure for
all the cylinders. It is not a good practice to mea-
sure the compression pressure for only one cylin-
der, and presume the compression for the
remaining cylinder.
(b) Also be sure to check engine speed when measur-
ing the compression pressure, as compression
pressure varies with engine speed.
(c) Measuring the compression pressure at regular in-
tervals is important to obtain correct data.
(d) On the new engine or overhauled engine, the
compression pressure rises temporary due to
breaking-in condition of the piston rings and the
valve seats. But it drops later due to the wear of
these parts.
(1)
Remove the glow plugs from all cylinders.
(2)
Attach the compression gauge adapter to the cylinder,
and connect compression gauge.
(3)
Crank the engine with the starter, then read the
compression gauge indication while the engine is
running at the specified speed.
(4)
If the compression pressure is lower than the limit,
overhaul the engine.
Note: (a) Measure the compression pressure with the
engine running at 150 to 200 min
-1
.
(b) Measure the compression pressure with the oil
and coolant temperature at 20 to 30°C [68 to
86°F].
Testing compression pressure
Item Standard Limit
Compression pressure
2.94 MPa
{30 kgf/cm²}
[427 psi]
2.55 MPa
{26 kgf/cm²}
[370 psi]
Gauge adapter
P/N:30691-21100
Compression
gauge
P/N:33391-02100