Chevrolet 30 Series 1967 Service Manual page 345

Fig. 4 —A ir M an ifo ld , Hose and Tube Routing
remove hose(s) and/or tube(s) as required.
CAUTION:
The 1/4" pipe threads at the cylin­
der head (In Line) or exhaust manifold (V
a straight pipe thread. Do not use a 1/4" tapered
pipe tap. The hoses of the A.I.R. System are a
special material to withstand high temperature.
No other type hose should be substituted.
• Install new hose(s) and/or tube(s), routing them as
when removed.
• Tighten all connections.
NOTE: Use anti seize compound on threads of
the air manifold to exhaust manifold or cylinder
head connections.
Check Valve
Inspection
• The check valve should be inspected whenever the
hose is disconnected from the check valve or when­
ever check valve failure is suspected. (A pump that
had become inoperative and had shown indications
of having exhaust gases in the pump would indicate
check valve failure).
• Orally blow through the check valve (toward air
manifold) then attempt to suck back through check
valve. Flow should only be in one direction (toward
the air manifold).
Replacement
• Disconnect pump outlet hose at check valve. Remove
check valve from air manifold, being careful not to
bend or twist air manifold.
Mixture Control Valve
Inspection
• Check condition and routing of all lines especially
the signal line. A defective signal or outlet line will
cause malfunctioning of the mixture control valve.
• Disconnect pump to valve inlet hose at pump.
• Leaking valve will be indicated by an air gushing
noise coming from the hose. Place palm of hand over
hose; little or no pull with a gradual increase is
normal. If immediate strong pull is felt or air noise
is heard, valve is defective and should be replaced.
• Open and close throttle rapidly. Air noise should be
evident and then gradually decrease.
proper valve usage. If strong pull is not felt im­
mediately or air noise is not present, valve is not
functioning properly and should be replaced.
• A noisy valve should be replaced.
Replacement
• Disconnect the signal line, air inlet and air outlet
hoses then remove the valve.
• Install new valve and connect air outlet, air inlet
and signal line hoses.
CAUTION:
sim ilar in appearance are designed to meet the
particular
therefore, be sure to install the correct valve.
Air Injection Tube
Inspection (Fig. 5)
• There is no periodic service or inspection for the
) are
8
AIR INJECTOR REACTOR SYSTEM 6T-3
Mixture c o n t r o l valves, though
requirements of various engines,
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