Chevrolet DB90 Series, Руководство по обслуживанию

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Sec. 7A -159
TRANSMISSON CONTROL LINKAGE
TRUCK MODELS WITH ALLISON A T540 AUTOM ATIC TRANSMISSIONS
LIN K A G E ADJUSTM EN TS
MANUAL RANGE SELECTOR LINKAGE
ADJUSTMENT (R efer to F ig. 11)
The manual s e le c to r linkage should fully en­
gage a ll tra n sm issio n range p o sitio n s just before
the le v e r h its the "stops" incorporated in the shift
control tow er. Shift the s e le c to r lev er through
each p osition w hile feelin g for fu ll engagem ent in
the tra n sm issio n . Note the p osition of the s e le c to r
le v e r a fter each sh ift. T ra n sm issio n should not
engage "D" (Drive) or "R" (R everse) until the
s e le c to r le v e r on control tow er is com pletely out
of the "N" (Neutral) notch. If le v e r is not properly
located or operating, the linkage should be adjust­
ed as follow s:
1. Locate tr a n sm issio n s e le c to r le v e r (B)
against stop in "N" p osition.
2. Check cable for dim ension shown in View
A -A , and adjust if n e c e ssa r y . Anchor cable to
b racket at point (D).
3. D isconnect c le v is (G) from manual shift
le v e r (H). Anchor cable (E) se c u re ly at point (F).
4. Locate manual sh ift le v e r (H) in "N."
NOTE: N eutral p osition of manual shift lev er
i s obtained by rotating le v e r com pletely forward,
then back one notch.
5. Adjust c le v is (G) for fr e e -e n tr y of c le v is
pin through c le v is and manual shift le v e r (H). Then
shorten cable by rotating c le v is 2 turns clock w ise.
Tighten jam nut against c le v is , in stall c le v is pin
and se c u r e with cotter pin.
6. A fter com pleting a ll adjustm ents, operate
v eh icle and check operation of the se le c to r le v e r
through a ll shift ra n g es. Readjust if n e c e ssa r y .
NEUTRAL SAFETY AND BACK-UP LIGHT
SWITCH ADJUSTMENT (R efer to Inset, F ig. 11)
NOTE: "Manual Range S elector Linkage Ad­
justm ent" should be p erform ed as d escrib ed p r e ­
vio u sly , p rior to adjustm ent of the neutral safety
sw itch.
1. B lock driving w h eels, apply parking brake,
and perform the follow ing to prevent the v eh icle
from accid en tally startin g w hile perform ing ad­
justment:
2. P u ll secondary w ire out of center socket
in distributor cap and ground w ire to prevent p o s ­
s ib le damage to c o il.
Figure 11—Typical M a n u a l Shift Linkage
IA T54 0 A utom atic Transm issionI
3. Move le v e r (B) to "N" (Neutral) p osition,
then referrin g to Inset (fig. 18), loosen jam nuts
and adjust length of push rod to dim ension shown.
4. With sw itch push rod properly adjusted,
tighten jam nuts se c u r e ly .
5. Check each range p osition of shift linkage
to make su re the sta r te r does not operate with
the s e le c to r le v e r in any position other than "N."
Have a ssista n t check for proper operation of back­
up ligh ts with se le c to r le v e r in "R." If n e c e ssa r y ,
readjust sw itch.
6. R econnect secondary w ire to distributor
cap.
NOTE: AT540 tra n sm issio n replacem ent procedures
a re found in "TRANSMISSION ON-VEHICLE SERVICE
OPERATIONS” (SEC. 7B) follow ing in this supplem ent.
CHEVROLET SERIES 70-90 HEAVY DUTY TRUCK SHOP MANUAL SUPPLEMENT