Chevrolet 1963 Corvette, Руководство по ремонту и настройке

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180 EMISSION CONTROLS AND FUEL SYSTEM
Plug the idle air passages of each throttle body as
shown
holding the brake pedal to prevent vehicle
movement. The engine rpm should decrease
below curb idle speed. If the engine rpm does
not decrease, check for a vacuum leak.
9. Remove the cap from the ported tube
on the rear TBI unit and connect a vacuum
gauge or water manometer.
10. Adjust the rear unit throttle stop screw
to obtain approximately Vz in. of mercury as
read on the vacuum gauge, or 6 in. of water
as read on the manometer. If not able to ad
just to this level, check that the front unit
throttle stop is not limiting throttle travel.
11. Remove the vacuum gauge or manom
eter from the rear unit and install the cap on
the ported vacuum tube.
12. Remove the cap from the ported vac
uum tube on the front TBI unit and install
the gauge or manometer as before. If the
reading is not the same as the rear unit, pro
ceed as follows:
a. Locate the throttle synchronizing
screw and collar on the front TBI unit. The
screw retaining collar is welded to the
throttle lever to discourage tampering with
this adjustment.
b. If the collar is in place, grind off the
weld from the screw collar and throttle le
ver.
c. Block possible movement of the
throttle lever as illustrated, relieving the
force of the heavy spring against the throt
tle synchronizing screw, to prevent the le
vers from coming into contact.
NOTE: If the lever is not blocked before
the throttle synchronizing screw is re-
moved, the screw may be damaged and
reinstallation will be done only with great
difficulty.
Block throttle lever movement as shown
d. Remove the screw and collar and dis
card the collar.
e. Reinstall the throttle synchronizing
screw, using thread locking compound.
f. Adjust the screw to obtain ¥2 in. of
mercury on the vacuum gauge, or 6 in. of
water on the manometer.
13. Remove the gauge or manometer from
the ported tube and reinstall the cap.
14. Adjust the rear throttle stop screw to
obtain 475 rpm, with the transmission in
DRIVE and the parking brake applied. On
manual transmission models, leave the gear
selector in NEUTRAL.
15. Turn the ignition OFF and place au
tomatic transmission in NEUTRAL.
16. Adjust the front throttle stop screw to
obtain .005 in. clearance between the front
throttle stop screw and the throttle lever tang.
17. Remove idle air passage plug$ and re
connect LAC valves.
18. Start the engine. It may run at a high
rpm but the engine speed should decrease
when the idle air control valves close the air
passages. Stop the engine when the rpm de
creases.
19. The throttle position sensor (TPS)
voltage should be checked and adjusted, if
necessary. See "TPS Adjustment" for proce
dures.
20. Install the air cleaner gasket, connect
the vacuum line to the TBI unit and install
the air cleaner.
21. Reset the idle speed control motors by
driving the vehicle to 30 mph.
Fuel Tank
REMOVAL AND INSTALLATION
CAUTION: Exercise extreme caution while
servicing the fuel tank. Service the tank only
in a well ventilated area. DO NOT smoke
BLOCK LEVERS
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