O.S. Engines 61RX-H WC - Manual (Page 9)

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.
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