O.S. Engines 70SZ-H - Manual (Page 5)

8
BASIC ENGINE PARTS
Heatsink Head
Carburetor Typr 60K
Crankshaft
Crankcase
Glowplug
Beam Mount
Cover
Plate
INSTALLATION OF THE CARBURETOR
Retainer screw
Carburetor Rubber Gasket
0.2mm gap
Loosen the retainer screw, rotate the carburetor to
its correct position and press it well down into the
intake boss, compressing the rubber gasket as
shown in the sketch, before re-tightening screw.
Rotate the retainer screw gently until it stops, then
tighten a further 120-180 degrees. Do not over-
tighten the screw as this will damage the thermo-
insulator.
Positioning Mark
Thrust Washer
Carburetor
Rubber Gasket
Carburetor
Sealing Washer
Carburetor Retainer
Carburetor Retaining
Screw
Fit the carburetor rubber gasket to the carburetor
body.
Insert the carburetor seal washer into the
carburetor fitting hole to the bottom.
Insert the carburetor retainer into the holes shown
left and fit the carburetor to the engine.
9
INSTALLING THE GLOWPLUG
Install the washer on the
glowplug and screw
carefully into cylinder-
head, making sure that it
is not cross-threaded
before tightening firmly.
Front view
CORRECT
Side view
Top surfaces are in the same plane.
Re-align the surfaces as necessary
INCORRECT
Top surfaces are not
in the same plane. Top surfaces are not in the
same plane.
Engine does not rest firmly.
Make sure that only the under-surfaces
of the engine’s mounting lugs are in
contact with the engine mount.
If the crankcase body touches the
mount, chamfer the edges of the mount.
INSTALLATION OF THE ENGINE
The under-surfaces of all O.S. engine beam
mounting lugs are precision machined flat and
exactyly parallel to the engine's horizontal axis. It is
essential that the engine mounts in the model are
also accurately made and aligned. If they are not,
they will cause stress and distortion within the engine
itself, probably resulting in loss of performance and
internal damage.
The recommended screws for securing the engine to
the engine mounts in the model are 4mm or 6-32 NC
steel Allen type. It is also advisable to use lock
washers or LOCTITE to prevent nuts from loosening.
Glow plug
Washer