EM0KB-06
- ENGINE MECHANICALCOMPRESSION
EM-3
424 Author: Date:
1996 TERCEL (RM440U)
COMPRESSION
INSPECTION
HINT:
If there is lack of power, excessive oil consumption or poor fuel
economy, measure the compression pressure.
1. WARM UP AND STOP ENGINE
Allow the engine to warm up to normal operating temperature.
2. REMOVE SPARK PLUGS (See page IG-1)
3. CHECK CYLINDER COMPRESSION PRESSURE
(a) Insert a compression gauge into the spark plug hole.
(b) Fully open the throttle.
(c) While cranking the engine, measure the compression
pressure.
HINT:
Always use a fully charged battery to obtain engine revolutions
of 250 rpm or more.
(d) Repeat steps (a) through (c) for each cylinder.
NOTICE:
This measurement must be done in as short a time as pos-
sible.
Compression pressure:
1,275 kPa (13.0 kgf/cm
2, 185 psi) or more
Minimum pressure:
980 kPa (10.0 kgf/cm
2, 142 psi)
Difference between each cylinder:
100 kPa (1.0 kgf/cm
2, 14 psi) or less
(e) If the cylinder compression in one or more cylinders is low,
pour a small amount of engine oil into the cylinder through
the spark plug hole and repeat steps (a) through (c) for
cylinders with low compression.
If adding oil helps the compression, chances are
that the piston rings and/or cylinder bore are worn
or damage.
If pressure stays low, a valve may be sticking or
seating is improper, or there may be leakage past
the gasket.
4. REINSTALL SPARK PLUGS
