TRUCK SERVICE MANUAL
Redundant Throttle Closing Linkage
The model 4150G carburetor, appearing on vehicles
produced after September 1, 1973, are equipped with
redundant throttle closing linkage as an added safety feature.
The purpose of this redundant linkage is to return the throttle
to the idle position in the event throttle return spring becomes
disconnected or linkage breaks.
The redundant linkage consists of a safety spring,
trip lever, retaining lever and throttle lever as shown in Fig.
26. Under normal operation the safety spring is held in a
coiled (loaded) position by the notch in the retaining lever and
tab of the trip lever. The throttle return spring supplies the
force necessary to keep the notch and tab engaged. In the
loaded position, the throttle lever may be operated with the
usual restraining force of the throttle return spring.
Figure 26 Redundant Throttle Closing
2. Notch and Tab Engaged
If the throttle return spring becomes disconnected,
the notch and tab will become disengaged allowing the force
of the loaded safety-spring to snap the throttle to the idle
position. Although vehicle may be driven in this condition, the
redundant throttle closing linkage should be reloaded as soon
exercised when servicing 4150 model
throttle closing linkage. Whenever the
throttle return spring is disconnected at
either end, the throttle linkage at the
carburetor will snap to a closed position
under a spring force sufficient to cause
personal injury. It is essential, to prevent
personal injury, that all instructions be
followed in the stated order and hands be
kept clear of carburetor throttle linkage
when connecting or disconnecting the
throttle return spring.
The overhaul procedure which follows can be
accomplished with ordinary tools. However, the use of
carburetor tool set SE-1772 is strongly recommended. Use of
the tools in this set not only protects parts which ordinary
tools might damage, but also saves time as well.
CGES-125-T Page 18
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