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21 - 52
AUTOMATIC TRANSMISSION
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(2) S t a r t a n d r u n the engine a t 1000 r p m .
(3) Move t h e valve body selector lever one detent
rearward f r o m f u l l f o r w a r d position. T h i s is 2 range.
(4) Move t h e transmission t h r o t t l e lever f r o m f u l l
forward t o f u l l r e a r w a r d position and read pressure
at both gauges.
(5) L i n e pressure should be 54-60 psi 372-414 kPa)
w i t h t h r o t t l e lever f o r w a r d and g r a d u a l l y increase t o
90-96 psi ( 621-662 kPa) as the lever i s moved rear-
ward.
Test Three-Transmission In D Range
T h i s test c h e c k s p r e s s u r e r e g u l a t i o n a n d c o n -
dition o f the front a n d r e a r c l u t c h c i r c u i t s .
(1) Connect test gauges t o the l i n e pressure and
front servo ports (Fig. 2).
(2) S t a r t a n d r u n the engine a t 1600 r p m for this
test.
(3) Move t h e selector lever two detents r e a r w a r d
from f u l l f o r w a r d position. This is D range.
(4) Read pressures on b o t h gauges as transmission
throttle lever i s moved f r o m f u l l forward to f u l l rear-
ward position.
(5) L i n e pressure should be 54-60 psi (372-414 kPa)
w i t h t h r o t t l e lever forward and g r a d u a l l y increase as
lever is moved r e a r w a r d .
(6) F r o n t servo is pressurized only i n D range and
should be t h e same as l i n e pressure w i t h i n 3 psi (21
kPa) u p t o downshift p o i n t .
Test Four-Transmission In Reverse
T h i s test c h e c k s p u m p output, p r e s s u r e r e g u l a -
tion a n d the front c l u t c h a n d r e a r s e r v o c i r c u i t s .
(1) Connect t h e 300 psi gauge to the rear servo port
(Fig. 3).
(2) S t a r t a n d r u n the engine a t 1600 r p m for test.
(3) Move t h e valve body selector lever four detents
rearward f r o m the f u l l forward position. This is Re-
verse range.
(4) Move t h e t h r o t t l e lever a l l t h e w a y forward
then a l l the way r e a r w a r d and note the gauge read-
ings.
(5) Pressure should be 145 - 175 p s i (1000-1207
kPa) w i t h lever forward and increase to 230 - 280 psi
(1586-1931 kPa) as lever is moved r e a r w a r d .
Test Five-Governor Pressure
(1) This test checks governor operation b y measur-
ing governor pressure response t o changes i n engine
speed. I t is u s u a l l y not necessary t o check governor
operation unless shift speeds are incorrect or i f the
transmission w i l l not downshift.
(2) Connect a test gauge t o the governor pressure
port (Fig. 3).
(3) Move t h e selector lever to D range.
(4) A p p l y brakes t o stop wheels. S t a r t and r u n t h e
engine a t c u r b idle speed a n d note pressure. A t idle,
pressure should be zero t o 1-1/2 p s i m a x i m u m . I f
pressure exceeds t h i s figure, the governor valve or
weights are s t i c k i n g open.
(5) S l o w l y increase engine speed a n d observe speed-
ometer a n d pressure test gauge. Governor pressure
should increase i n p r o p o r t i o n to vehicle speed. Or ap-
p r o x i m a t e l y 1 psi for every 1 m p h .
(6) Pressure rise should be smooth a n d drop back t o
0 t o 1-1/2 psi w h e n wheels are stopped.
(7) Compare results o f t h e pressure tests w i t h t h e
analysis c h a r t (Fig. 4) .
TEST CONDITION
INDICATION
line pressure OK during
any one test
Pump and regulator valve OK
Line Pressure OK in R
but bw in D, 2, 1
Leakage in rear dutch area (servo,
dutch seals, governor support
seal rings)
Pressure OK in 1, 2 but
bw in D3 and R
Leakage in front dutch area (servo,
dutch seals, retainer bore, pump
seal rings)
Pressure OK in 2 but bw in
R and 1
Leakage in rear servo
Front servo pressure in 2
Leakage in servo; broken servo
ring or cracked servo piston
Pressure bw in all positions
Clogged filter, stuck pressure
regulator valve, worn or
defective pump
Governor pressure too high at
idle speed:
Governor valve sticking open
Governor pressure bw at all
mph figures
Governor valve sticking dosed
Lubrication pressure low at all
throttle positions
Clogged oil cooler or lines, seal
rings leaking, output shaft
plugged with debris, worn
bushings in pump or dutch
retainer
J9021-34
Fig. 4 Pressure Test Analysis Chart
CONVERTER STALL TEST
S t a l l t e s t i n g involves d e t e r m i n i n g m a x i m u m en-
gine r p m obtainable a t f u l l t h r o t t l e w i t h the rear
wheels locked and t h e transmission i n D range. T h i s
test checks t h e h o l d i n g a b i l i t y o f t h e the converter
o v e r r u n n i n g clutch a n d b o t h o f t h e transmission
clutches. W h e n s t a l l t e s t i n g is completed, refer to the
S t a l l Speed Specifications c h ar t and S t a l l Speed D i -
agnosis guides.
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