Volvo 164, 1970 Service Manual page 266

Fig . 6-63. Pressure gauge connected
INSPECTING THE SERVO STEERING
VOLVO
103 163
The inspection proced ure described below ca n be
app li ed w ith a view to fa ult trac ing or pre ventin g
possib le f a ults.
I.
Checki ng the outer ceil i ng
l . Chec k to make sure th at a lll sc rew uni o ns are not
da mage d. Reti g hten if necessary .
2. Chec k the hoses fo r da mag e. Repl ace those that
are damaged.
II. Checking oil level and venting
l. Connect th e test instrument SYO 2864 to the de-o
livery line at the steering box, see Fig. 6-63. The
inlet hose of the instrument is connected to the
banjo nipple with tool SYO 2865 (Fig . 6-63) and
the outlet hose to the steering box with tool SYO
2866. Check to make sure that the operating lever
of the instrument is in the open position (to the
left).
2. Jack up the front end of the vehicle. Check that
the oil level is
5- 10
mm
(1/4")
above the level
mark with the engine stationary.
3. Start the engine. Check the level, and fill with oil
if the level has fallen below the level mark with
the engine running. Turn the steering wheel from
full lock to full lock as long as air bubbles are
visible in the container. With the engine idling,
the oil level should be at the level mark.
4. When the engine is stopped, the oil level should
rise
5- 10
mm
(1/4").
III. Checking the hydraulic function for stee ri ng box
and pump
l. Run the engine warm.
2. Pump testing: With the engine idling, move the
operating lever of the instrument briefly (max. 10
6: 30
seconds ) to the closed position. Read off the max.
press ure on the pressure-ga uge. This shou ld be
maximum 10
%
be low t he indi ca ted max imum
pressure of th e pump, that is, at least 67 kg/cm 2
(953 Ib/sq.in. ). If press ure less tha n t hi s is obta ined,
examine th e pump and drive as fo ll ows:
a) Check t he tens io n and co nd ition of th e drive
belL Re pl ace th e belt if def ective.
b) Re move t he pum p con troi· va lve, se e Fig. 6-64.
O bserve th e utmost clea nlin ess. W as h a nd
b low cle an befo re sc rewing out the plug (4,
6-67), wh ich shoul d be done f rom un de rn eath.
Check t he va lve piston a nd drillin g in th e
ho using . The ho le in t he va lve p isto n must not
be b lo cked. The p iston sho ul d run eas ily in the
ho using and not jam .
If
necessary, f ii" a new
va lve. If t hi s does not help, re pl ace or recon -
d ition the p ump.
3. Steering box test: W ith t he eng in e id lin g a nd t he
inst rum ent o pera tin g lever o pen, tu rn th e stee rin g
wh ee l to the rig ht to th e end position. Increa se
t he fo rce o n the steering w heel, to about 10 kg
(22 Ib.) a nd ma inta in thi s position for about 5
se con ds a nd read of the gauge. Repeat thi s pro-
cedure afte r turning the steering wheel to the left.
If it is established that the steering box oil pres-
sure, with the steering wheel turned either to the
right or to the left or in both directions, is below
the previously determined oil p ressure for the
pump, then the function of the servo steering is
not satisfactory. If no externai leakage can be
discove red, the reason for the pressure drop must
be an internai leakage, in which case the steering
box must be replaced.
IV. Checki ng the mecha nical f unctio n
l. Check the mechanical components of the front
end and steering such as ball joints, rods, bear-
ings, steering box and flanges concerning play.
Re -tighten attaching bolts and replace damaged
or worn components.
Fig. 6-64. Removing the controi valve
1. Pisfon 2. Spring 3. Gasket 4. Plug