O.S. Engines 21VZ-M - Manual (Page 14)

26
CARE AND MAINTENANCE
Engine maintenance is very important for good
running next time. Carry out the followings.
Do not forget to clean the filters regularly to
remove dirt and lint that accumulate on the
filter screens. Also, clean the carburetor itself
occasionally.
At the end of each operating session, drain
out any fuel that may remain in the fuel tank.
Afterwards, energize the glowplug and try to
restart the engine, to burn off any fuel that
may remain inside the engine. Repeat this
procedure until the engine fails to fire. Leav-
ing fuel residues within the engine can result
in difficult starting after a period of storage. It
may also cause corrosion. To reduce such
risks, it is helpful to inject some corrosion in-
hibiting oil into the engine's air intake. Rotate
the engine many times to distribute the oil to
all the working parts.
Drain the water remaining in the water cool-
ing head, and wash out with methanol, then
inject corrosion-inhibiting or moisture-dis-
placing oil.
When cleaning the exterior of the engine,
use methanol or kerosene. Do not use gaso-
line or any solvent that might damage the sil-
icone fuel tubing or any plastic parts of the
boat hull.
When the engine is not in use remove the
glowplug and rinse out the interior with kero-
sene (not gasoline), by rotating the crank-
shaft. Shake out residue, then inject light ma-
chine-oil through the plug hole again rotating
the shaft to distribute the protective oil to all
working parts.
In the event of water having entered the cy-
linder, crankcase, etc., refer to the proce-
dures recommended in the footnote to
"running-in" section.
Avoid unnecessary disassembly of your engine.
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After long use, the engine will not develop the
standard performance due to wear of parts. It
is suggested to replace the parts, such as ball
bearings, connecting rod, cylinder & piston
assembly and crankcase, as necessary after
checking when the following symptoms are
found.
CHECKING OF THE ENGINE
Idling gets unstable and/or the engine stops
at idling.
Engine sound changes and the engine tends
to overheat.
Power drops extremely.
GUARANTEE
This engine is constructed from the very best
materials available and to the very highest
engineering standards, using the most
advanced precision machinery. However, the
extremely high stresses imposed by car racing
operation under very severe conditions, as
well as stresses which are exacerbated by the
use of powerful fuels containing very high
concentrations of nitromethane, constitute
hazards which are beyond a manufacturer's
control. Accordingly, we regret that it is not
possible to extend our usual warranty terms to
this particular engine -i.e. no guarantee is
offered against material wear, or damage
resulting therefrom, in actual use.