Subaru 1600 Service Manual page 307

AUTOMATIC TRANSMISSION AND DIFFERENTIAL
2) Rear differential
The rear differential is unchanged
from the SUBARU 1800 4WD (manu-
al type). The difference in gear ratio
with the front side differential is
adjusted by the transfer gear (gear
ratio 37/39 = 0.948) so that the front
and rear wheels will rotate at the same
speed.
3) Transfer clutch control circuit
The transfer clutch circuit and transfer
valve have been added to the line
pressure circuit between the oil pump
discharge side and control valve. Along
with this change, the oil supply circuit
to the torque converter and the lubri-
cating circuit to the clutch and plane-
tary gear portions have been partially
modified.
AT for 83 MY
AT for 82 MY and before
Torque converter
Lubrication
to rear
portion
-r.:::::::;;t---I"""rr (c1 utches)
Oil
cooler
X
Lubrication
to front
portion
(planetary
one-way
clutch)
X Drain
'*
Restriction
Transfer (4WD)
Oil
r---------,
pump
I
I
I
Torque converter
portion
(planetary
one-way
clutch)
Pressure
Oil pump
Lubrication
regulator
valve1~~~~
A13-403
Fig. 7-8 Comparison of hydraulic circuits
4) Transfer valve
The transfer valve is an of -off valve
which opens and clbses the line pres-
sure circuit to the transfer clutch, and
this valve is operated by the solenoid.
In the FWD mode, the solenoid push
rod and valve are set at the right side
by the spring positioned on the left
side, and the line pressure to the
clutch is disconnected.
If the solenoid is energized by depress-
ing of the 4WD selector switch, the
push rod is activated and the valve is
pressed to the left against the pressure
of the spring. As the valve is moved,
the transfer clutch circuit opens while
the drain circuit closes, and the line
pressure is led to the transfer clutch
circuit to engage the transfer clutch.
Transfer clutch Line pressure
A13-404
Fig. 7-9 Transfer valve
7-12
I III 11" .'''~4
....... -." .....
".-' 1 ' ' 4 1-' ' ' ' ' ' ' ' ' ' ' ' ' ' _ _
1'''''''''''1t ... , _____ - - -__ •...
,q _ _
fJ1"'---_______________
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