O.S. Engines 91SZ-H - Manual (Page 8)

14
INSTALLATION OF THE CARBURETOR
1.
2.
Retainer screw Carburetor Rubber
Gasket
0.2mm gap
Carburetor Rubber
Gasket
INSTALLATION OF THE STANDARD ACCESSORIES
Retainer screw
Carburetor Retainer
Insert the carburetor rubber
gasket on the carburetor
body securely.
Then, insert the carburetor
in the crankcase.
Note: In case it is hard to insert the carburetor in
the crankcase, apply oil on the carburetor body.
Do not force it, or damage the carburetor body
and/or crankcase.
Insert the carburetor retainer as illustrated.
Unscrew the retainer screw a little.
Rotate the retainer screw gently until it stops, then
tighten a further 90-120 degrees.
Do not over-tighten the screw as this will damage
the carburetor body. 3.
15
INSTALLING THE GLOWPLUG
Install washer on glowplug
and insert carefully into
Heatsink-head, making sure
that it is not cross-threaded
before tightening firmly.
Glow plug
Washer
The knurled heads of the two needle valves (High-
Speed and Medium Speed) are provided with
diagonal slots for use with a screwdriver.
Alternatively, formore positive location via an Allen
hexagonal key, these heads also have M2.6 internal
threads, into which M2.6x5mm Allen cap-head screw
may be installed. To avoid risk of damage to the fuel
passages when tightening these screws, remove the
needle valves from the carburetor and use 'Loctite'
thread-lock compound to secure the screw.
HEX KEY NEEDLE ADJUSTMENT
ABOUT THE HEAD GASKET
ABOUT THE WOODRUFF KEY
Needle Adjusting screw
The engine is installed with a 0.2mm thick head
gasket at the factory. If necessary according to the
fuel used, atmospheric conditions and glow plug
used, adjust the thickness with the extra 0.2mm and
0.1mm gasket supplied with the engine.
Use the woodruff key supplied with the engine if the
fan pulley of the model has a groove to accept it.