Table of Contents
Advertisement
19 - 44
STEERING
•
PRESSURE TEST
The f o l l o w i n g procedure can be used to test the op-
eration o f the power steering system while i n s t a l l e d
on the vehicle.
S a f e t y
g o g g l e s s h o u l d b e w o r n a t a l l t i m e s
w h e n i n v o l v e d w i t h p o w e r s t e e r i n g p u m p p r e s -
s u r e t e s t i n g .
(1) Check and adjust the power steering p u m p belt
tension as necessary. I f necessary, refer to the proce-
dure.
(2) Place a d r i p p a n under the engine and discon-
nect the power steering pump h i g h pressure hose ei-
ther a t the p u m p or a t the steering gear (whichever
is t h e most convenient). M a i n t a i n t h e hose e n d
raised above the reservoir to prevent fluid loss.
(3) Connect Pressure Test Gauge Tool C-3909E t o
the pump pressure hose and to an adapter hose (use
an a d d i t i o n a l adapter hose i f necessary). Connect the
test gauge between the power steering p u m p and the
steering gear (Fig. 2).
Fig. 2 Pressure
Test
Gauge
CAUTION: Ensure that the test gauge is connected
in the fluid pressure circuit between the pump and
the steering gear.
(4) Open t h e test valve
completely. Rotate t h e
valve counterclockwise to open i t .
(5) F i l l the fluid reservoir w i t h power steering f l u i d
as necessary.
(6) Insert a thermometer i n the fluid reservoir. Op-
erate
t h e engine
u n t i l
t h e power
steering
f l u i d
reaches the n o r m a l operating temperature of 66°C to
77°C (150°F to 170°F).
T u r n i n g t h e w h e e l s
f r o m " s t o p - t o - s t o p "
w i l l
a i d w i t h h e a t i n g t h e f l u i d . D o n o t h o l d t h e steer-
i n g w h e e l a g a i n s t t h e " s t o p " f o r a n e x t e n d e d pe-
r i o d o f t i m e b e c a u s e t h i s w i l l cause t h e p u m p t o
o v e r - h e a t a n d d a m a g e i n t e r n a l c o m p o n e n t s .
(7) W i t h t h e engine at a speed of approximately
600 to 800 r p m and the gauge valve open, the i n i t i a l
pressure should be i n the range o f 207-345 k P a (30-
50 psi) a n d should definitely be less t h a n 690 k P a
(100 psi). I f the pressure is 690 k P a (100 psi) or
more, inspect the hoses for restrictions and repair as
necessary.
CAUTION: The following test procedure involves
testing the maximum pump pressure output and the
flow control valve operation. Do not close the test
gauge valve for more than five seconds at a time
because this could damage the pump.
(8) Close t h e test gauge valve f u l l y , t h e n i m m e d i -
ately open i t . Repeat t h i s procedure three times and
record t h e highest pressure indicated o n t h e test
gauge each t i m e the test gauge valve is closed.
(9) Compare the highest indicated pressures. I f the
pressure indications are a t least 8 900 k P a (1,300
psi) a n d t h e variance o f the three pressure indica-
tions is w i t h i n the 345 kPa (50 psi) allowable v a r i -
ance, t h e p u m p is functioning n o r m a l l y .
F o r e x a m p l e : i f t h e h i g h e s t i n d i c a t e d p r e s s u r e s
a r e 8 930 k P a , 8 990 k P a a n d 9 050 k P a (1,305
p s i , 1,315 p s i a n d 1,325 psi), t h e y a r e a c c e p t a b l e
a n d , b e c a u s e t h e p r e s s u r e v a r i a n c e i s w i t h i n t h e
345 k P a (50 p s i ) a l l o w a b l e v a r i a n c e , t h e p u m p
o p e r a t i o n i s n o r m a l .
(10) I f t h e highest indicated pressures are more
t h a n the acceptable l i m i t of 9 930 kPa (1,450 psi) for
pressure r e l i e f or the pressures are not w i t h i n t h e
345 k P a (50 psi) allowable variance, the flow control
valve is n o t functioning correctly. Remove a n d clean
the valve (Fig. 3). Remove burrs w i t h a crocus cloth
or a fine g r i t hone. I f the system is contaminated,
flush
i t .
FLOW
CONTROL
VALVE
J8919-65
Fig. 3 Flow Control
Valve
Advertisement
Table of Contents
