Westerbeke ATOMIC 4 User Manual

small, round brass disc riveted
,to the car!Juretor.
The Zenith carburetor supplied
on the l.Iodel 250, 155 II. P. Knight
may require adjustment of the
throttle plate stop scre'w "An at
the full throttle position (See
Fig. 69.) This carburetor is some-
'7hat sensit ive to the thrott Ie
plate positioning in that if it
goes slightly past the vertical
POSition, it will upset fuel dis-
tribution in the ~anifold and cause
~~ l!Iar!ced decrease in engine p017er
and speed at full throttle. The
carburetor is correctly set on en-
gines tested at the factory, but
replacement carburetors '"/ill have
to be adjusted in the field.
l7ith the carburetor attached and
the engine ready to run, loosen
the stop screw "A" until it does
not contact the stop pin f'B" with
the throttle lever "c" at the full
throttle position' as sho~m in Fig.
69. In this position the cast lug
on the throttle lever should touch
the stop pin. Now with the engine
running at full throttle, close
the throttle very slowly and care-
Fig.68
Carburetor - Adjustoents
-53-
fully observe the reaction of the
tachometer. If the tachometer shows
a steady decrease as the throttle
is retarded, the stop screw is not
needed in adjusting the carburetor.
Ho~ever, if the tachometer first
increases to a maximum and then
falls off as the throttle is re-
tarded, the stop screw must be used
to correctly position the throttle
plate as follo'rls: Find the thrott Ie
position that will give maximum en-
gine RP:U and stop the engine without
disturbing the throttle setting.
Screw the stop screw in until it
just touches the stop pin. Restart
the engine and check to see that
it uill still attain its peak RPU
as noted before the adjustment. It
would be preferable if the adjust-
ment or setting of the stop screw
't7as made with the engine running,
but this is not possible or advis-
able in many installations.
Always take every precaution against
fire hazards when working around
your fuel system. Be sure to dis-
connect batteries; do not turn on
flashlights, operate electric
switches or turn over the starter
or generator.
THROTTlE LEVER "C" IN
FULL THROTTLE POSITION ~_J
Fig.69
Carburetor - Adjustments

Westerbeke ATOMIC 4 Specifications

General

Brand	Westerbeke
Model	ATOMIC 4
Category	Engine
Language	English