Pontiac FIREBIRD 1972 Service Manual page 1056

' 6 - 18
1972 PONTIAC SERVICE MANUAL
Figure 7G-20 1-2 Shift Valve
2-3 SHIFT VALVE
Routes oil pressure that causes the transmission to shift
from 2-3 or 3-2. Its operation is controlled by governor,
detent and modulator shift valve pressures as well as a
spring force (Fig. 7 6 - 2 1).
Fig. 7G-21 2-3 Shift Valve
EXH.
I
Fig. 7G-22 Detent Valve
I V
Fig. 76-23 Detent Regulator Valve
DETENT VALVE
The detent valve, actuated by a cable connected to the
accelerator lever assembly, directs the regulated modula-
tor pressure tending to hold the 1-2 shift and 2-3 shift
valves in the downshift position and provides areas for
modulator and detent regulated pressures for detent 2-1,
3-1 and 3-2 downshifts (Fig. 76-22).
The detent regulator valve and spring regulate line pres-
sure into detent regulator oil which is used to control the
car speed at which the 1-2 and 2-3 upshifts occur (Fig.
76-23).
COOLER BY-PASS VALVE
The cooler by-pass valve permits oil to be fed directly from
the converter to the lubrication circuit when the oil is very
cold or if the cooler or lines should become restricted.
(Fig. 76-24).
- - .
+
TO
RADIATOR COOLER
Fig. 7G-24 Cooler By-Pass Valve