Opel 1900 1973, Service Manual

Page: 399 / 625

Figure Quadrant In Park Position 1900
and Manta
38 1973 OPEL SERVICE MANUAL
R Reverse enables the vehicle to be operated in a
reverse direction.
N Neutral position enables the engine to be
started and operated without driving the vehicle.
D Drive range is used for all normal driving
conditions and maximum economy and has three
gear ratios. Downshifts are available for passing
by depressing the accelerator partially at lower
car speeds and through the “detent” at higher car
speeds.
S or 2 Second range adds new performance for
hilly terrain. It has the same starting ratio as Drive
range, but prevents the transmission from shifting
above second gear to retain second gear for
acceleration or engine braking as desired. Second
range can be selected at any vehicle
but
should not be used above the speed shown the
Owner’s Manual. This is to prevent over-speeding
the engine. The transmission will shift to second
gear immediately and remain in second until the
vehicle speed or the throttle position is changed
to gear operation in the same manner
as in Drive range.
L or 1 Lo range can be selected at any vehicle speed,
but should not be used above the speed shown in the
Owner’s Manual. The transmission will shift to low
(1st) gear immediately and remain in 1st gear regard-
less of vehicle speed or throttle position. This is par-
ticularly beneficial for maintaining maximum engine
braking.
PRINCIPLES OF OPERATION
T o r q u e C o n v e r t e r
The torque converter acts as a coupling to transmit
engine torque, through oil, to the transmission power
train. It also multiplies the torque from the engine
under certain conditions of input and output speed.
Figure Quadrant in Park Position GT Models
The
quadrant
has
six positions indicated in the
fol-
lowing order: (Opel 1900 and Manta) P,R,N,D,S,
and L (Figure
and (GT) and 1
(Figure 2).
The torque converter used in the Opel three speed
automatic transmission consists of three basic ele-
ments: the pump (driving member), the turbine
(driven or output member) and the
(reaction
member). See Figure The converter cover is
welded to the pump to seal all three members in an
oil tilled housing.
P Park position enables the transmission output
shaft to be locked thus preventing the vehicle
from roling either forward or backward. Because
the output shaft is mechanically locked by a
parking
anchored in the extension housing,
the park position should not be selected until the
vehicle has come to a stop. The engine may be
started in the Park position.
Whenever engine is running, the converter pump
turns at engine speed and acts as a centrifugal pump,
picking up oil at its center, adding energy, and dis-
charging the oil at its outer rim between the blades.
The shape of the converter pump shells and blades
cause the oil to leave the pump spinning in a clock-
wise direction toward the blades of the turbine. As
there is no mechanical connection
between
pump and turbine, the oil is the only driving force
and strikes the blades of the turbine, transferring