O.S. Engines 18CV-RX - Manual (Page 11)

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BALL LINK AND SLIDE VALVE EXTENSION
It is seldom necessary to separate the slide-valve
extension from the slide-valve itself. For cleaning,
withdraw this complete sub-assembly from the
carburetor body after removing the slide-valve guide
screw. Then wash with methanol or glow-fuel.
(Note: take care not to lose the guide screw;it is a
special one.) When it is necessary to adjust the ball-
link position, loosen the ball-link retaining screw with
a 3mm hexagon key, re-align the ball-link and re-
tughten the screw firmly.
REALIGNMENT OF MIXTURE CONTROL VALVE
In the course of making carburetor adjustments, it is
just possible that the Mixture Control Valve may be
inadvertently screwed in or out too far and thereby
moved beyond its effective adjustment range. Its
basic position can be found by first rotating the
Mixture Control Valve until its slotted head is flush
with the carburetor body. The valve is then screwed in
exactly 1.5 turns to re-establish its neutral position.
Mixture Control Valve
Carburetor Body
First rotate the Mixture Control
Valve until its slotted head is
flush with the carburetor body.
Then screw the valve in exactly
1.5 turns (0.8mm).
This is the standard position.
CARBURETTOR CLEANLINESS
The correct functioning of the carburetor depends on its small fuel orifices remaining clear.
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4.
CARE AND MAINTENANCE
1.
2.
3.
The minute particles of foreign matter, that are
present in any fuel may, by accumulating and
partially obstructing fuel flow, cause engine
performance to become erratic and unreliable.
O.S. 'Super-Filters' (large and small) are available,
as optional extras, to deal with this problem.
One of these filters, fitted to the outlet tube inside
your refueling container, will prevent the entry of
foreign material into the fuel tank. It is also
recommended that a good in-line filter be installed
between the tank and carburetor.
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 glow-plug 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. Do this while the engine is still
warm.
Then, inject some after-run oil into the engine, and
rotate the engine with an electric starter for 4 to 5
seconds to distribute the oil to all the working
parts.
Note:
5.
Do not inject after-run oil into the carburetor as
this may cause the O-rings inside the carburetor
to deteriorate. These procedures will reduce the
risks of starting difficulties or corrosion after a
period of storage.
Finally, when cleaning the exterior of the engine,
use methanol or kerosene. Do not use gasoline or
any solvent that might damage the silicone fuel
tubing.
Caution:
The rear crankshaft bearing of this engine uses a
special plastic retainer. If the front housing needs
to be heated to remove or replace the bearing, do
not allow the bearing to exceed 120˚C (248˚F),
otherwise it may be damaged and rendered
unserviceable.