Air Cleaners - GMC 4000 Series Service Manual

3. Push hand throttle completely in, then loosen
trunnion screw and move wire trunnion to make
light contact with hand throttle lever. Tighten trun­
nion screw, then check operation of hand throttle.
Air cleaners used on models covered by this
manual are equipped with one of the following types
of air cleaner elements:
1. Oil Bath
2. Oil Wetted Paper
3. Dry Type - Paper
Air cleaners must be serviced at regular in­
tervals as specified in LUBRICATION (SEC. 0) in
this manual, or more frequently for extensive
operations in dusty areas.
All clamps and connections between air clean­
er and carburetor must be kept tight at all times
to prevent unfiltered air from entering the carbur­
etor.
On In-line engines, a pleated paper-type filter
is used at carburetor as illustrated in figure 6. The
filter element should be replaced after first 500
m iles of service and at periodic intervals there­
after, depending on cleanliness of fuel.
On V-6 engines, a disposable line-type filter
is used. This filter is located between the fuel
G M C S E R V I C E M A N U A L
Figure 4 — Accelerator Linkage (Tilt Cab M o d els)
If properly adjusted, initial movement of hand
throttle control handle will cause increase in en­
gine speed; and when handle is pushed in, engine
will return to idle speed.

AIR CLEANERS

with dirt or sludge, the flow of air to carburetor
will become restricted causing increased fuel con­
sumption, loss of power, and possible damage to
engine. Air cleaner on vehicles operating in dust
storm areas should be cleaned immediately after
such storms occur.
equipped with In-line engine. The heat stove is
mounted at the exhaust manifold and allows pre­
heated air (heated by the manifold) to be drawn
through the heat stove to the air cleaner where it
is mixed with cold air drawn into the air cleaner
opening. This warm air mixture is then drawn into
the engine.
FUEL FILTERS
pump and carburetor and should be replaced at
12,000 mile intervals.
used on models covered by this manual. This filter
uses a disposable paper-element which should be
replaced at 12,000 mile intervals.
FUEL SYSTEM— GASOLINE ENGINES
If air cleaner is allowed to become clogged
A heat stove (fig. 5) is used on all models
An optional frame-mounted fuel filter may be
Sec. 6M
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