Chevrolet BEAUVILLE SPORTVAN G10 SERIES, Руководство по обслуживанию

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EMISSION C O N TR O L SYSTEM 6T-3
COMPONENT DESCRIPTION
Idle Stop Solenoid
The idle stop solenoid is a tw o positio n electrically oper­
ated co n tro l, used to provide a pred eterm in ed th ro ttle setting
(Fig. 6T-5). In the energized position (plunger extended) the
plunger co n tacts th e carburetor th ro ttle lever and prevents full
closing o f th e ca rb u re to r th ro ttle plates. This fast idle control
w hen de-energized (plunger retracted ) allows th ro ttle plates to
close b ey o n d the norm al idle p osition; th ereb y shutting o ff air
supply and in essence starving th e engine so th a t it will shut
dow n w ith o u t dieseling. T he idle stop solenoid is bracket-
a ttac h ed to the carb u reto r so th a t th e plunger, w hen exten d ed ,
contacts the th ro ttle lever.
CEC Solenoid
T he CEC solenoid (Fig. 6T-5) is a tw o-position electrically
o p erated co n tro l, w hich serves a dual fu n ctio n in th e TCS
system . In th e de-energized p o sitio n the spring loaded plunger
closes the vacuum supply p o rt to th e d istrib u to r advance unit
and opens the air ven t to th e advance u n it. In th e energized
position the plunger is ex ten d e d to co n tac t th e carburetor
th ro ttle lever and to open th e vacuum p o rt to th e distrib u to r
and to shut o f f th e air vent. The solenoid is b rac ket-attached
to th e carb u reto r so th a t th e plunger, w hen extended, contacts
the th ro ttle lever to m aintain a p red e term in e d engine RPM.
Time Relay
T he tim e relay is an electrically o p erated on -o ff type
sw itch. When th e coil is energized it begins to heat the bi-m etal
strip to open the norm ally closed relay p o ints in ap p ro x i­
m ately 20 seconds. A ground p a th is provided for th rough the
Fig. 6 T -6 —L-6 Tem perature Cold Override Switch
re la y h o u sin g a n d m o u n tin g b ra c k e t. T w o se lf-ta p p in g
screw s a tta c h th e rela y to th e v ertic a l w all o f th e cow l
b elo w th e b r a k e m a in cylin d er.
Temperature Cold Override Switch
The cold override sw itch, located in th e th e rm o stat housing
(Fig.
6
T-
6
) serves to activate th e CEC solenoid. A t coolant
tem peratures below 82 (± 7 ) degrees, th e cold term inal is
co ntacted by the bi-m etallic strip to ground and com pletes the
circuit to th e CEC solenoid. In th e neutral position, no con tact
is m ade; th erefo re th e circuit is bro k en .
Transmission Switch
On m anual shift synchrom esh transm issions, b o th 3- and
4-speed, th e sw itch is located on the outside o f the trans­
mission case in an area adjacent to the 2-3 o r 3-4 shifter shaft,
as applicable (Fig. 6T-7). T he m echanically operated sw itch is
spring loaded to provide c o n tin u ity betw een th e switch ter-
Fig. 6 T -5 — L-6 Idle Stop & CEC Solenoids Fig. 6 T -7 —Transmission Switch Location (M anuall
TCS TEMPERATURE SWITCH
C H E V Y V A N S H O P M A N U A L