Locating Gasoline Gauge Troubles; Removing T A N K Unit - Cadillac 1937 LaSalle VVI Information

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E L E C T R I C A L
will not require readjustment unless they have
been tampered with. In cases of poor horn tone,
the difficulty will ordinarily be found to result
from one of the following causes:
Low B a t t e r y — M a k e sure that the battery is in
good condition and fully charged also that the
battery connections are clean and tight.
P o o r E l e c t r i c a l Contacts — C h e c k the con-
tacts to make sure they are not burned or dirty.
H o r n Relay Faulty—Make sure the relay is
operating properly.
Projectors Interchanged—The projector and
power unit must be properly matched. T h e short
projector should be installed on the power u n i t
marked " S " the long projector on the u n i t m a r k e d
" L " . These markings appear on the front of the
power unit cover. See F i g . 29.
Fig. 29. Horn Relay and Adjustments
In most cases, a defect in the tone can be cor-
rected by checking the above points. If not, the
air gap between the armature and the field should
be checked as a last resort. T h i s gap requires
extremely accurate setting and should not be
touched u n t i l all other possibilities have been
exhausted.
If the air gap is out of adjustment; it should be
set parallel w i t h i n .003 inch a n d to the following
limits:
L o w note 045 to .050 inch
H i g h note 036 to .040 inch
G A S O L I N E G A U G E
20. Locating Gasoline Gauge T r o u b l e
Does Not Register When Ignition Switch Is
Turned " O N "
I. T h i s m a y be caused b y break i n line between
dash unit and ignition switch.
G a u g e Shoius "Full" Under All C o n d i t i o n s
1. This m a y be caused by break i n line between
dash unit and tank unit. T o remedy this, check
line and a l l connections.
2. T a n k u n i t burned out. Replace tank unit.
3. T a n k u n i t improperly "grounded" due to
loose mounting screws or paint under the screw
heads.
Tighten screws holding the tank unit. " G r o u n d "
the tank to the chassis and test.
Gauge Shows "Empty" Under All Conditions
1. T h i s m a y be caused by wires being reversed
on dash unit. T o correct this trouble, reattach
wires to proper terminals.
2. D a s h unit not "grounded." G r o u n d or
replace dash unit.
3. Lead to tank u n i t grounded or t a n k u n i t
rheostat continually grounded.
Gattge Inaccurate Throughout Entire Range
T h i s condition may indicate the need for read-
justment of the lock screw for the magnetic coils
operating the needle. T h e lock screw is o n the
bottom of the dash unit on the left h a n d side.
T o readjust, loosen the screw and re-set to the
correct readings. It is, of course, necessary to
have a float unit in the circuit and to recheck the
readings by filling the tank.
In some instances, incorrect readings are due
to a bent floaCarm. T h e remedy in this case is
bending the a r m back to its n o r m a l position.
The work in locating the trouble will be con-
siderably simplified if an extra tank unit is
available as this can be connected u p temporarily
w i t h the gauge by a short piece of wire, - and
grounding the body tank unit to the chassis.
The float can then be moved to the " F u l l " and
" E m p t y " positions. If the dash unit indicates the
corresponding positions, the trouble is confined
to the tank unit and wiring.
21. Removing T a n k U n i t
T o remove the tank unit proceed as follows:
1. Remove tail pipe brackets.
2. Disconnect gas line.
3. Loosen gas tank straps and drop gas tank.
4. Disconnect wire from'unit.
5. R e m o v e unit.
Caution: D o not lubricate either the dash or tank
units. N o lubrication is necessary in the
dash unit and the bearings in the tank
unit are automatically lubricated by the
splash of gasoline.
W h e n connecting wires to dash unit, make cer-
tain that the wire which leads to the tank u n i t
does not come in contact with the ammeter con-
nection or the terminal on clash unit marked
" i g n i t i o n " as this m a y result- in damage to the
tank unit rheostat.