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Note
Once the correct carburettor settings have been established, it
should be unnecessary to alter them. Such slight needle-valve
readjustments as may be required to compensate for variations in
atmospheric conditions will not normally affect the other two
controls. Slight readjustments may be necessary for optimum
performance if different types of fuel, glowplugs or propellers
are used.
VENTURI INSERT
This carburettor is fitted with a venturi insert for general
use. If, however, higher power output is required, it is
permissable to remove the insert.
Mixture Control Screw
Venturi Insert
Mixture Control
Valve Set-screw
Do not remove this nut.
HOW TO REMOVE THE VENTURI INSERT
1. Unscrew the Throttle Stop Screw and withdraw the
throttle rotor.
2. Remove the Mixture Control Valve Set-screw and care-
fully withdraw Mixture Control Valve.
3. Extract the venturi insert.
4. Reassemble the carburettor.
CARBURETTOR CLEANLINESS
The correct functioning of the carburettor depends on its
small fuel orifices remaining clear. The minute particles of
foreign matter that are present in any fuel can easily partial-
ly obstruct these orifices and upset mixture strength so that
engine performance becomes erratic and unreliable.
It is recommended that fuel is passed through a filter when
the tank is filled and that a good in-line filter is installed
between the fuel tank and carburettor and, furthermore,
that this filter is frequently cleaned to remove dirt and lint
that accumulates on the filter screen. Finally, occasionally
remove the needle-valve holder from the carburettor as
shown in Photo (2) and extract any remaining foreign
matter that may have lodged in the location shown in
Photo (3).
Mixture Control
Valve
Rotor
Dirt and fibrous matter
mostly accumulate here
PARTS LIST
Photo (2)
Photo (3)
The specifications are subject to alteration lor improvement without notice.
Description
Mixture Control Screw
Mixture Control Valve
"0" Rings
Throttle Rotor
Mixture Control Valve Set-screw
Throttle Lever
Universal Link
Throttle Stop Screw Assembly
Throttle Stop Screw
Throttle Stop Screw Holder Assembly
Nipple No 1
Carburettor Body
Carburettor Rubber Gasket
Needle Valve Assembly
Needle Valve Holder Assembly
Ratchet Spring
Needle
"0" Ring
Set-screw
Remove this with
8mm spanner
Code No.
26681603
29081305
24881824
29081200
26881311
26881406
26881424
27181600
27181620
27181610
22681953
29081110
29015019
27381900
27381940
26711305
29081952
24981837
26381501
6-15 3-chome Imagawa Higashisumiyoshi-ku
Osaka 546, Japan. TEL (06) 702-0225
FAX. (06) 704-2722
©Copyright 1992 by O.S. Engines Mfg. Co., Ltd. All rights reserved. Printed in Japan.
60130080-19710