OPEL 1900 1973 Service Manual

7C- 701973 OPEL SERVICE MANUALd

d. Operation of Controls in Drive Range Third Geat
Reverse Clutch ReleasedThird Clutch-Applied
Second Clutchs AppliedLow Band Released
Sprag Locked
As vehicle speed increases. the governor allows more oil to pass through to act against the wring
at the 2 3 shift valve. This allows the second clutch oil at
the 2 3 shift valve
10 be released and pan through the valve as third clutch oil, directed tothe third clutch piston to apply third clutch. At the same time,
third clutch oil is directed
to the 3 2 control valve. acting against the spring and modulator oil. cutting off modulator oil pressure to the 2. 3 shift controlyalve. Third control oil also is directed to the Reverse and Law control valve and pasts through thevalveasservo release oil to the lowspeed downshift
timing valve. The low speed downshih timing valve is held
open against the spring by increased modulator oil pressure. The oil passes through the valve and
is directed
to the top of the low band sewo. to act with the servo piston spring and force the sel~o piston downward. releasing the low band.
The second clutch is on, the third clutch is on, the band is released. The transmikn is in drive range third gear

7C- 721973 OPEL SERVICE MANUAL

e. Operation of Controls in Second Range Second Gear
Reverse Clutch
Re easedThird Clutch Released
Seconds Clutch AppliedLow Band Applied
Sprag Over Running
The
selector lever is moved to the Intermediate position an the quadrant. the manual valve is positioned to allow drive oil and Intermediate oilto pan through the valve. Intermediate oil is directed
to the pressure regulator boost control cavity, seating the check ball at the reverse passage.Intermediate oil is then directed to the pressure regulator valve downward to
increaSe the oil prepare in the circuit. At the same time. the inter.
mediate oil from the manual valve is directed lo the 2 3 shift valve train closing off the supply of third clutch oil in the circuit, which isexhausted
through the Reverse and Low control
valve.
SummaryWith third clutch oil exhausted. the third clutch is off, the second clutch is an, the low band
servo is applied. The transmission is in second
Range Second Gear.

7C- 741973 OPEL SERVICE MANUAL

f. Operation of Controls in Low Range First GeaReverse Clutch ReleasedThird Clutch Applied
Second Clutch Released
Low Band Applied
Sprag Locked
When the
selector lever is moved to the low position on the quadrant. the manualvalve is positioned to allow drive oil, intermediate oil and low oil to pass
through the valve. Low oil is directed to the
1 2 shift valve train which acts with the I 2 shift valve spring against governor oil pressure to close off drive
oil from passing into the second clutch passage. At the
same time, low oil is directed to the Reverse and Low control valve and acts against the spring to
allow detent regulated oil at the Reverse and Law control
valve to flow to the 2 3 shift valve, which is bottomed in its bore by intermediate oil pressxeand the valve spring. The detent oil
pazses through the 2 3 shift vahre and into the third clutch oil passages to apply the third clutch and to close off
modulator oil pressure from the 3-2 control valve to the 2 3 shift control valve. Third control oil isalSo directed to the Reverse and Law control
valve.which is held open against its spring by low oil pressure. and closes off the
source of rupply to the servo release pasege. to allow the servo to apply the low
band. Intermediate oil seats the check ball at the Reverse
passage at the presue regulator boost valve cavity and continues to the pressure regulator valve
to increase oil pressure in the circuit.
iThe third clutch in on, the band is on. The transmi&n is in Low Range First Gear

712.761973 OPEL SERVICE MANUAL

9. Operation of Controls in Reverse
Reverse Clutch -Applied
Second Clutch Released
Sprag LockedThird Clutch. Applied
Low Band. Released
When the selector leer is moved to the Reverse position on the quadrant, the manual
valve ispositioned to allow Revert oil to pars through the manual
valve into the
Reverse oil passage. The reverse oil applies the reverse clutch. and a portion is directed to the priming valve which acts as a damper until the
line is filled. to effect a smooth and firm apply of the
reverss clutch. At the wne time, reverse oil is directed to the pressure regulator boost control valve
cavity to seat the check ball and prevent reverse oil pasring into the intermediate oil passage. It is then directed to the pressure regulator boast valve forcing
Reverse oil is also directed to act on the end of the
Reverse and Law control valve against the spring to allow detent regulated oil to pass through the valveto the 2 3 shift
valve. The detent regulated oil passes through the 2 3 shift valve and into the third clutch oil passages to apply the third clutch. The third
clutch oil
al= acts on the end of the 3 2 control valve against the spring and modulator oil pressure, clodng off the supply of modulator oil to the 2 3
shift control valve. Third clutch oil at the rwerse and low control valve is closed off from
parring through the valve. and into the servo releal~ parrage.Summary
The
reverse clutch is cm and the third clutch is on. The transmission is in Reverse Range.

a1973 OPEL SERVICE MANUAL

h. Operation of Controlr during Detent Downshift Valves in Second Gear Position
Reverse Clutch Released
Second Clutch Applied
Sprag Over RunningThird Clutch Released
Low Band Applied
With the selector in the Drive position. detent downshifts ore possible by fully depressing the accelerator pedal. This causes the mechanical linkage to the
detent
velve to move the detent valve, cutting off moduahor oil to the 3 2 control valve, the 1 2 shift control valve, the 1 2 accumulator valve and the
2 - 3 shift control velve.The mechanical linkage holding the detent nlve open allows the detent regulated oil to pass into the detent oil
passdgeand is directed to the 2 3 shift
control
valve. acting against the spring and governor oil pressure. It is also directed to the 3 2 control valve. acting against the spring, allowing detent oil to
pass through the valve and act on the end of the 2 3 shift control valve to keep the valve bottomed in its bore again* governor oil pressure. Second clutch
oil et the 2 3 shift
valve is closed off from passing into the third clutch passages by the detent oil pressure holding the 2 3 shift valve bottomed in its bore.
Summary
The second clutch is on, the low band is on. The valves are in
wand gear position under detent conditions.