O.S. Engines 7H Carb - 23781011 - Manual (Page 2)

After the engine is fully run-in and/or when a different fuel is used,
it may be necessary to change the screw positions very slightly.
Idle Mixture Control Screw
THROTTLE STOP SCREW
Rotate this screw to obtain the required idling speed: counter-clockwise
to reduce idling speed, clockwise to increase idling speed/The adjust-
ment can be held firmly by gently tightening the locknut.
Leaner
THROTTLE LEVER
Three different throttle arms are provided. Fit the one most appro-
priate to your installation.
Leaner
Mid-range Mixture Control Screw
THROTTLE RETURN SPRING
This ensures a taut, smooth-working throttle linkage. It will also return
the throttle rotor to the idling position in an emergency, i.e. in the
event of the throttle linkage becoming disengaged. Richer
NEEDLE-VALVE EXTENSION
The needle-valve fitted to this carburettor is designed to accept an
extension arm so that, when the engine is enclosed within a helicopter
fuselage, the needle-valve may be adjusted from the outside. An L-
shaped steel wire rod of approximately 1.6 mm (or 1/16") dia. and
appropriate length, should be inserted into the centre-hole and secured
by tightening the set-screw in the control-knob with the small Allen
key wrench provided.
INCORRECT THROTTLE LEVER THROW
Fig-3
PARTS LIST
Description
Throttle Lever (W/Screw & Washer)
Bearing Retainer (L)
Bearing Retainer (S)
Rotor Bearing
Return Spring
Carburettor Rotor
Throttle Stop Screw Assembly
Rotor Stopper
Rotor Stopper Holder Assembly
Return Spring Fitting Screw
Carburettor Body
Carburettor Rubber Gasket
Idle Adjusting Valve Assembly
"0" Ring
Plug Screw (W/ Gasket)
Fuel Inlet (W/ Gasket)
Idle Mixture Control Screw (W/Spnng)
Mid-range Mixture Control Screw (W/Spring)
Idle Adjusting Valve Stopper
Needle Valve Assembly
Needle Valve Holder Assembly
Ratchet Spring
Needle (with 0 ring & Set-screw)
"0" Ring
Set-screw
The specifications are subject to alteration for improvement without notice.
27381400
27381120
27381220
27381210
27381130
27381201
27181600
27181620
27181610
27381140
27381111
29015019
27381301
24881824
22081304
22681953
27381330
27381350
27381340
27381900
27381940
26711305
29081952
24981837
26381501
SET LINKAGE SO THAT THE ANGLES OF THE LOW
SIDE AND THE HIGH SIDE OF THE THROTTLE
LEVER THROW ARE EQUAL.
Low High
to servo
idling speed (or stop)
Fig-2
Low
High
Low
High
Richer
6-15 3-chome Imagawa Higashisumiyoshi-ku
Osaka 546, Japan. TEL. Osaka (06) 702-0225
58508