Chevrolet 30 Series 1967 Service Manual page 332

ENGINE FUEL 6M-8
fingers or other suitable means. Slight "seepage"
around the seals is not abnormal; however, a vac­
uum gauge reading within
that can be obtained with the vacuum hose
"squeezed" should be possible if the seals are in
satisfactory condition. If the seals leak exces­
sively they should be replaced.
c. When the spinner parts are reassembled, they
should be wiped with a rag saturated with light oil
to provide slight, but not excessive lubrication.
3.
If actuator or tubing trouble is indicated:
a. Remove the vacuum tube at the actuator, run the
engine at about 3000 rpm and place a finger over
the end of the actuator. If there is no change in
engine operation, probably the actuator is at fault.
A significant change in engine rpm would indicate
General Description.........................................................
Maintenance P r o c e d u r e s ................................................
Element R ep lacem en t................................................
Testing Paper E l e m e n t .............................................
Air cleaners on all models operate primarily to re­
move dust and dirt from air before it is drawn into the
carburetor and engine. The air cleaner also helps to
reduce engine noise and quenches any flame that may be
caused by engine backfire through the carburetor.
Three types of air cleaners are used on 1967 Chevrolet
trucks. They are the oil wetted paper element air
cleaner, the two element air cleaner and the oil bath air
cleaner.
The oil wetted paper element air cleaner (fig. 1A) con­
sists of an accordian pleated oiled paper filter supported
by wire mesh with a plastisol seal on both top and bottom.
The two element air cleaner (fig. 2A) consists of an oil
wetted polyurethane band wrapped around an oil wetted
paper element.
The oil bath air cleaner (fig. 3A) utilizes an oil sump
in the air cleaner bottom and a fibre element.
On most applications of the two element air cleaner it
OIL RESISTANCE
SEAL
BONDED PAPER
BOTTOM
ELEMENT
Fig . 1A - Paper Element A ir Cleaner
" hg. of the maximum
2
AIR CLEANERS
INDEX
Page
6M-8
6M-9
6M-9
6M-9
GENERAL DESCRIPTION
COVER
tube leakage and tube should be replaced.
If the tubing is alright, check the actuator unit for
leakage. With the orifices "stopped up" with the
fingers, or other means, no leakage should occur.
Also check for proper seal of diaphragm cover
and condition of diaphragm itself.
governor housing can be checked by removing the
connection to the distributor and attaching a vac­
uum line. If there is no vacuum reading check
the diaphragm for holes and be sure the vacuum
passage is clear.
c. If no leakage is found, clean all of the component
parts.
If tampering is suspected, visually check parts
with the governing parts of an engine that is gov­
erning properly.
Tool J-7825 ..................................................................
Cleaning Polyurethane B a n d ....................................... 6M-10
Cleaning Oil Bath C l e a n e r .......................................... 6M-11
is used in conjunction with an exhaust manifold heat stove
(fig. 4A). Air temperature is automatically controlled by
a thermostatic valve which selects warmed air from the
heat stove and/or cooler air from the engine compart­
ment or from outside the vehicle.
Diesel engine applications require the use of several
types of oil bath air cleaners. All types are serviced in
a manner sim ilar to the gasoline engine oil bath air
cleaners.
Fig . 2A - Two Element A ir Cleaner
Vacuum in the
Page
6M-10
CHEVROLET TRUCK SERVICE M ANUAL