30
CARBURETOR CARE & MAINTENANCE
If you experience difficulty in obtaining a
consistent mixture setting it could be due to
foreign debris in the carburetor. Carefully
disassemble the carburetor and wash in
methanol. Do not use gasoline or kerosene
that can effect the silicone rubber "O" rings.
Debris tends to accumulate in
this area
Mixture Control Valve
Carburetor Body
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.
Rotate the Mixture
Control Valve until its
slotted head is flush
with the carburetor
body. This is the
standard position.
31
VALVE ADJUSTING
CARE AND MAINTENANCE
Please pay attention to the matters
described below to ensure that your engine
serves you well in regard to performance,
reliability and long life.
As previously mentioned, it is vitally important
to avoid operating the engine in conditions
where dust, disturbed by the propeller, may
be deposited on the engine and enter its
working parts.
Remember to keep your fuel container
closed to prevent foreign matter from
contaminating the fuel.
Install a fuel filter to prevent dirt and foreign
matter in the fuel container from entering the
fuel tank. O.S. Super Filters (L) and (S) are
available as optional extras.
Valve clearances are correctly set before
any O.S. engine leaves the factory and, in
normal use, will seldom require adjustment.
However, if, after a considerable amount of
running time, a loss of power is detected, or
if he engine has been disassembled for
repair, these clearances should be checked
and reset as necessary. Clearance should
be 0.04mm - 0.1mm (.0015" - .004")
For checking and adjusting the valve
clearances, a VALVE ADJUSTING TOOL
KIT is available as an optional accessory.
Also, a 5.5mm wrench (not supplied) is
required for this purpose.
• Feeler gauge 0.04mm
The kit comes in a plastic case and includes:
(Code No.72200060)
• Feeler gauge 0.1mm
• Hex. key 1.5mm • Wrench 5mm
• Wrench 5.5mm
