Removing And Checking The Fuel Gauge; Checking The Voltage Stabilizer - Volvo 164, 1970 Service Manual

checked by co nneding t he sen der cab le to t he car
c ha ss is as t his will da mage th e in strume nt mec ha ni sm
(to o high a voltag e , o n ' the in strum e nt res iSJto r and
overheating of the bimetal spring ). If no ohmmet' e r is
availab le, the above teSlt can be carried out by placing
a 10 ohms resistance between the sender cable and
the ground connection on the chass is.
The sender shou ld also be checked with an ohmmeter.
Resistance in the sender should , at room temperat ure ,
be approximately 200 ohms.
The indi cnting in strumen, t can also be checked by
connection to a 12 vo lt battery, via a voltage stabil i-
zer, and with a pr, e vious ly checked pickup coupled
in series. On heating the sender both the instruments
shou ld show a correspond ing temperatur' e . A check
can su itably be made with a thermomet, e r (sender and
thermometer s ubm ersed in heated water). Checking
values are as follows:
Beg inning of green area (at (liC")
At d ividi ng line between green areas
At d ividing line between green and
40° C (105° F)
70° C (150° F)
red areas 100° C (212° F)
If
check ing is carried out with on instrument which is
mounted on the in strument plate, then a
12
v,olt supply
sh ou Id be connected to terminal 2 on the instrument
plate (seie wiring diagram), the sen der to terminal 8
and the ground ca ble to terminal 16. Do not forget
to ground the sender.
REMOVING AND CHECKING
TH E FU EL GAUGE
The pickup and fuel gauge are not repairable and
must be exchanged if faulty or damaged.
The gauge can be removed from the detached instru-
ment panel when the voltage stabilizer and rheostat
Fig. 3·98. Pickup for fuel gauge
_ SVO 2738
Fig. 3·99. Tool for removing pickup
have been loosened and the nuts to the instrument are
accessible. The fuel gauge should be checked with
an ohmmeter. The resistance should be approx. 12.5
ohms. Measurement can suitably be carried out
between the nuts on the rear side of the instrument
plate.
Checking of the gauge by connecting the pickup lead
to earth is not permitted as this will damage the
gauge (excessive loading on the resistor wire and
overheating of the bimetal spring). If no ohmmeter is
available the test can be carried out by connecting
a 10 ohms resistor between the lead and grounding
point on the chassis.
The pickup, Fig. 3-98, can be removed af ter the carpet
and wooden fibre board in the luggage compartment
have been lifted out. The pi'ckup is atrrached by means
of a bayonet fitting. When removing, use tool SVO
2738 as shown in Fig. 3-99. The pickup
should be
checked with an ohmmeter.
At the upper stop the pickup should have a resistance
of approx. 10 ohms and
a, t the lower, approx.
60- 85
ohms. Movement of the float a'rm should not result
in a break in the circuit (reading).
CHECKING THE VOLTAGE STABILlZER
The voltage stabilizer, shown ,
i n Fig. 3-100, is aMached
to the reverse side of the comhined instrument by a
screw. After the screw has been loosened, the sta-
bilizer can be pulled out from the contact pin holes
3 : 41