Chevrolet 10 Series 1967, Руководство по обслуживанию, Страница: 346 / 605

AIR INJECTOR REACTOR SYSTEM 6T-4
air injection tubes, yet on In Line engines whenever
the cylinder head is removed or on V
8
engines when­
ever the exhaust manifolds are removed, inspect the
air injection tubes for carbon build up and warped or
burnt tubes.
• Remove any carbon build up with a wire brush.
• Warped or burnt tubes must be replaced.
Replacement
• On In Line engines remove carbon from tubes and
using penetrating oil, work tubes out of cylinder
head.
• On V
8
engines clamp exhaust manifold in a vise,
remove carbon from tubes and using penetrating oil,
work tubes out of manifold.
• Install new tubes in cylinder head or manifold.
Air Injection Pump
Inspection
Accelerate engine to approximately 1500 RPM and ob­
serve a ir flow from hose(s). If air flow increases as
engine is accelerated, pump is operating satisfactorily.
If air flow does not increase or is not present, proceed
as follows:
• Check for proper drive belt tension.
• Check for a leaky pressure relief valve. Air may be
heard leaking with the pump running.
NOTE: The A.I.R. System is not completely
noiseless. Under normal conditions noise rises
in pitch as engine speed increases. To deter­
mine if excessive noise is the fault of the Air
Injection Reactor System, operate the engine
with the pump drive belt removed. If excessive
Fig. 6 —Removing Pressure R e lie f V a lv e
Fig. 7— Installing Pressure R e lief V a lv e
noise does not exist with the belt removed
proceed as follows:
• Check for a seized Air Injection Pump.
• Check hoses, tubes, air manifolds and all connec­
tions for leaks and proper routing.
• Check carburetor air cleaner for proper installation.
• Check air injection pump for proper mounting.
• If none of the above conditions exist and the air in­
jection pump has excessive noise remove then repair
as outlined in the Overhaul Manual.
Replacement
• Disconnect the hoses at the pump.
• Remove pump pulley as outlined.
• Remove pump mounting bolts and remove pump.
• Install pump with mounting bolts loose.
• Install pump pulley as outlined.
• Install and adjust belt as outlined.
• Connect the hoses at the pump.
Pressure Relief Valve Replacement
1. Using J - 7055-5 and J-6585 pull relief valve from
housing (fig.
6
).
2. Using a 15/16" socket tap the relief valve into hous­
ing until the valve shoulders on the housing (fig. 7).
CAUTION:
Use extreme care to avoid distort­
ing housing.
NOTE: Various length pressure setting plugs
(fig.
8
) designed for the particular requirements
of vehicle - engine combinations, determine the
CHEVROLET TRUCK SERVICE M ANUAL