Cessna 150 Series - BATTERY; DESCRIPTION; REMOVAL AND INSTALLATION; CLEANING THE BATTERY

16-13.
TROUBLE
SHOOTING
THE BATTERY
POWER
SYSTEM.
(CONT.)
TROUBLE
PROBABLE CAUSE
REMEDY
BATTERY WILL NOT
SUPPLY Faulty
contactor or wiring
3. Measure
voltage at master
POWER
TO BUS OR IS INCAP-
between contactor
or master
switch terminal
(smallest) on
ABLE OF CRANKING
ENGINE. switch.
contactor
with master switch
(CONT.)
closed. Normal
indication is
zero volts.
If voltage
reads
zero,
proceed
to step 4.
If a
voltage reading is obtained
check wiring between contactor
and master switch. Also check
master
switch.
Open coil
on contactor.
4. Check continuity
between
"BAT" terminal and master
switch
terminal of
contactor.
Normal indication is 16 to 24
ohms (Master
switch open).
If ohmmeter indicates an open
coil, replace
contactor.
If
ohmmeter
indicates
a
good
coil,
proceed
to step
5.
Faulty contactor contacts.
5. Check voltage
on "BUS"
side of
contactor
with
master
switch closed.
Meter
normally
indicates
battery
voltage.
If
voltage is zero or intermittant,
replace
contactor.
If voltage
is normal, proceed to step 6.
Faulty
wiring between
con-
6. Inspect
wiring between
con-
tactor and
bus.
tactor
and bus.
Repair or re-
place wiring.
16-14. BATTERY.
d. Discount
the cable from the positive terminal
of the battery.
16-15. DESCRIPTION. The battery is
12 volts and e. Lift the battery out
of the battery box.
is approximately 25 ampere-hour
capacity. The bat- f. To replace
the battery, reverse this procedure.
tery is mounted
on the forward side
of the firewall
and is equipped with non-spill
filler caps. 16-17. CLEANING
THE BATTERY. For maximum
efficiency the
battery and connections
should be kept
16-16. REMOVAL
AND INSTALLATION (Refer
to clean at all times.
figure 16-2.)
a.
Remove the battery and
connections in accor-
a. Remove top half
of cowl.
dance with the preceding
paragraph.
b.
Remove the battery box
cover.
b. Tighten
battery cell filler caps
to prevent the
c. Disconnect the
ground cable from the
negative cleaning
solution from
entering the cells.
battery terminal.
c. Wipe the battery cable ends, battery terminals
and the entire surface of the battery with a clean
cloth
moistened
with
a solution
of bicarbonate
of
soda (baking soda) and water.
* When
installing or removing
battery always
d. Rinse with clear
water, wipe off excess
water
observe
the proper
polarity
with the aircraft
and allow
battery
to dry.
electrical
system (negative to
ground). Re-
e. Brighten up
cable ends and battery
terminals
versing
the polarity,
even
momentarily,
may
with emery
cloth or
a wire brush.
result in failure
of semiconductor
devices
f. Install the battery
according to the preceding
(alternator
diodes, radio protection
diodes paragraphs.
and
radio transistors).
g. Coat the battery
terminals with
petroleum jelly
or an ignition
spray product to reduce
corrosion.
*Always
remove the battery
ground cable
first and replace it last to prevent acci- 16-18. ADDING ELECTROLYTE OR WATER TO THE
dental short circuits.
BATTERY.
A battery being charged and discharged
16-4