O.S. Engines 21XZ-B - Manual (Page 10)

18
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.
Chamfer inside edges of bearers.
Do not allow bottom
of crankcase to
touch chassis.
Note:
Be sure to use a collet supplied when use a
optional 28XZ Hyper Flywheel Set.
The engine bottom may interfere with chassis
of some models. In this case, file off the
chassis so that the engine may not interfere
with the chassis when it is installed.
NOTE
19
STARTING THE ENGINE & RUNNING-IN ('Breaking-in)
PRESSURIZED FUEL SYSTEM
Before starting the engine, always
check the tightness of all the screws
and nuts especially those of joint and
movable parts such as throttle arm.
Missing retightening the loose screws
and nuts often causes the parts break-
age that is capable of harming you.
Never run your vehicle without installing the air
cleaner. Dust and dirt that may otherwise be drawn
into the engine will rapidly shorten its life.
The somewhat violent changes of vehicle attitude
that occur in off-road running, combined with the
fact that, in buggy type cars, the fuel tank is often
located some distance from the carburetor, means
that fuel 'head' at the carburetor can vary and upset
running.Therefore,it is recommended that a muffler
pressurized fuel feed system be used.
Running- in is a procedure for an engine to come
close to actual running conditions (fuel, r.p.m.,
engine temperature, etc.).
Excessively rich running and prolonged low
speed running should be avoided. Prolonged low
speed running and low temperature running may
result in the oil in the fuel becoming gelled and
the piston/liner becoming stuck together.
RUNNING-IN ('Breaking-in)