Chevrolet 10 Series 1970 Service Manual page 636

ACCESSORIES 15-6
M AG NET H O U S IN G
ASSEMBLY
TO SPEEDOMETER
FROM
TRANSMISSION
SOLENOID COIL
SIDE VIEW SECTION
SERVO
SERVICE
— If the S ervo unit is found to be d efe c tiv e, r e ­
placem ent is req u ired . N ote the condition o f the hoses
and rep lace any which
ADJUSTMENT
— ust the bead chain so that it is as tight
as p ossib le without holding the th rottle open when the
ca rb u retor is set at its low est idle th rottle position.
When connecting the bead chain (engine stopped) manually
set the fast id le cam at its low est step and connect the
chain so that it does not hold the idle screw o ff the cam.
If the chain needs to be cut, cut it three beads beyond the
bead which pulls the linkage.
REGULATOR
M A IN T E N A N C E
A d e fe c tiv e regu lator, that is one which
is not sim ply out o f adjustment, must be replaced. D ur­
ing replacem en t, check
the regu la tor and rep la ce
d eterio rated .
ADJUSTMENT
One regu la tor adjustment is possib le:
C ru isin g Speed Z e ro in g
tween engagement and cru isin g speed).
NOTE: No regu la tor
made, h ow ever, until the follow in g item s have
been checked o r se rv ic e d .
1. Bead chain p ro p e rly adjusted.
2. A ll hoses in good condition, p ro p e rly attached, not
M AG NET
SPEED DISC
FIELD PLATE
HAIRSPRING
SOLENOID & CLUTCH
HO U S IN G ASSEMBLY
SPEED SWITCH
ENGINE V A C U U M
CONNECTOR
VA C U U M VALVE
LOCK-IN CA M
SOLENOID PLUNGER
AIR FILTER
F ig . 8 — R egulator - Cross S e c tio n
a re cracked o r d eteriora ted .
the hoses which connect
any which are cracked o r
Engagem ent-
(to rem ove any d ifferen ce b e ­
adjustment should be
END VIEW SECTION
leaking, not pinched o r kinked.
3. E le c tr ic and
adjusted.
E N G A G E M E N T-C R U IS IN G SPEED ZEROING
I f the cru isin g speed is lo w e r than the engagement
speed, loosen the o r ific e
turn the tube outward; if higher, turn the tube inward.
Each 1/4 turn w ill a lte r the en gagem en t-cru isin g speed
d iffe ren c e one mph. Tighten the locknut a fte r adjustment
and check the system operation at 60 M PH .
ELECTRICAL SYSTEM CHECK OUT
1. Check fuse and connector.
2. Check e le c tr ic brake switch as follo w s: Unplug con­
n ector at switch.
B on brake switch. The oh m m eter must indicate in­
to
fin ity when the pedal is d epressed and continuity
when pedal is
switch (e le c tr ic ) is adjusted as is the standard stop
light brake switch. R eplace e le c t r ic brake switch if
needed.
3. Check engagem ent switch and connecting w irin g as
follow s: Unplug engagement sw itch connector (brown,
blue, black) at e le c tr ic a l w irin g harness connector
and p e rfo rm the fo llow in g tests. (See fig . 9).
T e s t #1 - Connect ohm m eter between term in a l #1
(brown w ir e ) and term in a l #2 (blue w ir e ). Continuity
shall be maintained until sw itch is dep ressed a ll the
way in.
T e s t #2 - Connect oh m m eter between term in al #1
CONTROL VALVE
CLUTCH SPRING
LOCKNUT
ORIFICE TUBE &
DNNECTOR ASSEMBLY
vacuum re le a s e sw itches
tube locknut (see fig . 8) and
Connect ohm m eter at points A and
relea sed . The cru ise re le a s e brake
CHEVROLET TRUCK SERVICE MANUAL
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