O.S. Engines 91SX-H Competition Special (P) - Manual (Page 5)

8
Because of initial tightness, a standard
electric starter may have difficulty in
rotating the engine when cold, before it
has been adequately run-in. In this
case, use a high-torque type starter.
DO NOT, however, confuse tightness
with the symptoms of hydraulic lock
caused by an excess of fuel within the
cylinder - often the result of over-
priming.
Attempting to force the engine to turn
over in this condition may cause
internal damage. Instead, remove the
glowplug, invert the engine and eject
surplus fuel from the combustion-
chamber.
Note:
This is a pumped version of the 91SX-H
RING C Spec. Pump and muffler
pressurized fuel system ensure stable fuel
supply irrespectire of model attitude and
fuel level in the tank. Return system in the
carburetor ejects the excess fuel and
avoids getting rich at around idling. Easy to
adjust single needly Type 60M carburetor
incorporates a check valve which controls
the fuel supply at any r.p.m. range.
INTRODUCTION
As delivered, the carburetor is not fit to
the engine.
Standard accessories
Glow Plug No.8 Woodruff Key
Needle Adjusting Screw (M2.6x5 1pc.)
Silicone tube
Note:
Carburetor Complete 60M
T nipple
Instruction manual
( 2.5x 5.5xL300mm)
9
BASIC ENGINE PARTS
Heatsink Head
Carburetor
Typr 60M
Crankshaft
Propeller nut
Crankcase
Thrust Washer
Glowplug
Beam Mount
Pump
As delivered, the carburetor is not fit to the engine.
Secure it as follows.
INSTALLATION OF THE CARBURETOR
Retainer Nut
Carburetor Rubber
Gasket
0.2mm gap
Loosen the retainer nut, press the carburetor well
down into the intake boss, compressing the rubber
gasket as shown in the sketch, before re-tightening
Nut.
Rotate the retainer nut gently until it stops, then
tighten a further 90-120 degrees. Do not over-
tighten the screw as this will damage the carburetor
body.
1.
2. Pump Holder
60M One-way Valve
Return Screw
Cover Plate
Press down until the gasket becomes almost invisible.