Testing Cylinder Compression; Cleaning Cooling Air Passages - Echo shindaiwa PB-8010 Service Manual

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7-1 Testing cylinder compression

D
Valve core 91039 (5 pcs)
B

7-2 Cleaning cooling air passages

B
A
C
A
ENGINE
NOTE: Test cylinder compression when engine is
cold.
1. Move ignition switch to STOP position.
2. Open cap cover and remove spark plug (Refer
to 3-2 Testing spark).
3. Remove valve core (A) from compression gauge
91037 (B) and insert valve core (A) to adapter
P021-051690 (C) with valve core driver (D).
4. Connect adapter (C) and compression gauge (B).
5. Install compression gauge 91037 (B) with adapt-
er P021-051690 (C) in spark plug hole and tighten
by hand. Pull starter several times to stabilize
reading on compression gauge.
6. If pressure is lower than approx. 75% of
standard compression pressure (Refer to "1-2
Technical data"), inspect cylinder bore, piston and
piston ring for wear or damage.
C
7. If pressure is more than approx. 125% of
standard compression pressure, inspect cylinder
combustion chamber and exhaust port, piston
crown, and muffl er for carbon deposits.
NOTE: Compression pressure varies with volume
of compression gauge tip occupying cylinder com-
bustion chamber. When you use other than the
tool 91037 (B) and adapter P021-051690 (C), it is
recommended to measure and note compression
pressure of brand-new engines as standard pres-
sure in advance.
NOTE: To maintain proper engine operating tem-
peratures, cooling air must pass freely through the
B
cylinder fi n area. This fl ow of air carries combus-
tion heat away from the engine.
1. Most of engine cooling come from blower fan
(A). Cooling comes through a large duct in the fan
housing. Clean accumulated debris from fan case
(B) with brush or compressed air as required.
WARNING
Always wear eye protection when using
compressed air for cleaning. Otherwise,
eye damage can occur from fl ying particles.
PB-8010, EB810
DANGER