O.S. Engines 21RZ-R (P) - Manual (Page 8)

ENGINE INSTALLATION
Make sure that the vehicle's engine mounting
surfaces are level and in the same plane. Poor
installation may cause distortion of the
crankcase, bearings, etc., resulting in erratic
running and loss of performance.
The recommended screws for securing the
engine are 3mm or 4-40 steel Allen hexagon
socket type.
If existing holes in the engine mount do not align
perfectly with engine mounting lugs, enlarge
them slightly with a needle-file so that screws are
in alignment with the mounting holes.
Chassis
Chamfer inside edges of bearers.
INSTALLATION OF THE CARBURETOR
As delivered, the engine has its carburetor lightly
fit into its intake boss. Secure it as follows.
Loosen the retainer screw, rotate the
carburetor to its correct position and make
sure that it is pressed well down into the
intake boss, compressing the rubber gasket,
before retightening screw. 1.
2. Rotate the
retainer nut
gently until
it stops.
Tighten a
further
90-120˚
Rotate the retainer
screw gently until it
stops, then tighten
a further 90-120˚.
Do not overtighten
the screw as this
will damage the
carburetor body.
INSTALLING THE GLOWPLUG
Fit washer to glowplug and
insert carefully into heatsink
head, making sure that it is
not cross-threaded
before tightening firmly.
Glow plug
Washer
7