O.S. Engines FS-52S - Manual (Page 22)

of contaminants as much as possible.
Do not leave unused fuel in the engine at the
conclusion of a day's flying. Accepted practice is to
cut off the fuel supply while the engine is still running
- at full throttle - then, to eliminate as much residue
as possible rotate the engine for 5-10 seconds with
the electric starter.
Finally, inject some after-run oil through the glowplug
hole and turn the engine over several times by hand.
When the engine is not to be used for some months
(for example, as between flying seasons) a
worthwhile precaution is to remove it from the
airframe and, after washing off the exterior with
alcohol (not gasoline or kerosene) to carefully remove
the fuel pump, carburettor with intake pipe and all
silicone tubing and put them safely aside.
Make sure that the engine is reasonably clean
externally, then remove the glowplug and immerse
the engine in a container of kerosene. Rotate the
crankshaft while the engine is immersed. If foreign
matter is visible in the kerosene, rinse the engine
again in clean kerosene, shake off the excess and
wipe it dry.
CARE & MAINTENANCE (continued)
The fuel pump assembly, carburettor/pressure-
regulator and silicone tubing must be cleansed
separately in methanol or glow fuel. On no account
must they come into contact with kerosene.
Before completely reassembling the engine, make
sure that no kerosene remains inside that could find
its way into the pump unit, carburettor, etc. Inject,
sparingly, after-run oils, rust inhibitors, etc. unless
approved for silicone-rubber products.
An appropriate alternative here may be one of the
high-quality synthetic lubricating oils.
Finally, seal the engine in a heavy polyethylene bag
until required for future use.
Debris tends to
accumulate in
this area
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