Tecumseh AH520 -, Руководство пользователя

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CYLINDER REED
REED
OPEN
COVER REED
PISTON
PIN
PISTON
REED
CLOSED
SINGLE
REED
EXHAUST
PORT
REED
OPEN
PISTON
PIN
PISTON
REED
OPEN
SINGLE
REED
EXHAUST
PORT
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CYLINDERS, REEDS & COMPRESSION RELEASE
CYLINDER & HEAD SERVICE . Check cylinder for
bore damage or scoring. Check for broken or cracked
fins, warped head or head mounting surface. If warped
extensively, (more than .005"/.127 mm) replace. Always
replace head gasket and torque to proper specification.
GASKETS. Replace all gaskets in reassembly and
make sure all sealing surfaces will not leak. A leaking
gasket will cause erratic running, hard starting and
could damage internal components by causing an
imbalance of fuel-oil air mixture.
REED VALVES. Make sure reeds and sealing surfaces
are free of dirt and foreign matter. Check reeds for
seal against sealing surface of the adapter. Reeds
should not bend away from sealing surface more than
.010'’ (.254 mm).
If the reeds are serviceable, the smooth side of the
reed must locate against the sealing surface. Service
reeds have “smudge” marks on smooth side. If these
marks are gone, feel for a rough edge and assemble
away from sealing surface.
AUTOMATIC COMPRESSION RELEASE (DOUBLE
REED TYPE).
Cranking compression pressures bleed past reeds
and into muffler. Once the engine is started, a high
pressure build-up between the reeds forces the reeds
against their seats stopping compression bleed off
and allowing engine to run at full compression.
TYPE I
TYPE II
TYPE II
Replace both reeds If either is defective. When installing
reeds be sure the colored side of the reed faces its
seating surface. If in doubt, feel for a rough edge on
the reed. The rough edge must be installed away from
the seating surface. Assemble reed stop and hold
down and tighten self-tapping screws.
Poor running or lack of power may be caused by a
leaking reed or cover gasket.
AUTOMATIC COMPRESSION RELEASE (SINGLE
REED TYPE).
Cranking compression pressures bleed past reed valve,
through a port, into the piston pin and out the exhaust
port.
As the engine starts and compression increases, the
reed will be forced against the bottom port, sealing it
and the engine will run under full compression.
Install the reed cover (single reed type) with the small
hole towards the spark plug.