Chevrolet 10 1971 Series, Chassis Service Manual

Page: 253 / 466

ENGINE-ELECTRICAL 6Y-3
Fig. 4b-Electrolyte at Low Level
rapid loss of water. If the electrolyte level is found to
be low, then colorless, odorless, drinking water should
be added to each cell until the liquid level rises to the
split vent located in the bottom of the vent well. DO NOT
OVERFILL because this will cause loss of electrolyte
resulting in poor performance, short life, and excessive
corrosion.
CAUTION:
During service only water should be
added to the Battery, not electrolyte.
The liquid level in the cells should never be allowed
to drop below the top of the plates, as the portion of the
plates exposed to air may be permanently damaged with
a resulting loss in performance.
WATER USAGE
Excessive usage of water indicates the Battery is being
overcharged. The most common causes of overcharge
are high Battery operating temperatures, too high a volt­
age regulator setting or poor regulator ground wire
connection. Normal Battery water usage is approximately
one to two ounces per month per battery.
CLEANING
The external condition of the Battery should be checked
periodically for damage or for the presence of dirt and
corrosion. Battery should be kept clean. An accumulation
of acid film and dirt may permit current to flow between
the terminals, which will slowly discharge the Battery.
For best results when cleaning Batteries, wash first with
a diluted ammonia or a soda solution to neutralize any
acid present, then flush with clean water. Care must be
taken to keep vent plugs tight, so that the neutralizing
solution does not enter the cells.
CARRIER A N D H O LD -DO W N
The carrier and hold-down should be clean and free
from corrosion before installing the Battery. The carrier
should be in a sound mechanical condition so that it will
support the Battery securely and keep it level.
To prevent the Battery from shaking in its carrier,
the hold-down bolts should be tight (60-80 in. lbs.).
However, the bolts should not be tightened to the point
where the Battery case or cover will be placed under
a severe strain.
SAFETY PRECAUTIONS
When Batteries are being charged, an explosive gas
mixture forms in each cell. Part of this gas escapes
through the holes in the vent plugs and may form an
explosive atmosphere around the Battery itself if venti­
lation is poor. This explosive gas may remain in or
around the Battery for several hours after it has been
charged. Sparks or flames can ignite this gas causing
an internal explosion which may shatter the Battery.
The following precautions should be observed to pre­
vent an explosion:
1. Do not smoke near Batteries being charged or which
have been very recently charged.
2. Do not break live circuits at the terminals of
Batteries because a spark usually occurs at the point
where a live circuit is broken. Care must always be
taken when connecting or disconnecting booster leads
or cable clamps on fast chargers. Poor connections
are a common cause of electrical arcs which cause
explosions.
CHARGING PROCEDURES
Before charging a battery, the electrolyte level must
be checked and adjusted if needed.
Battery charging consists of applying a charge rate in
amperes for a period of time in hours. Thus, a 10-ampere
charge rate for seven hours would be a 70 ampere-hour
(A.H.) charging input to the battery.
Charging rates in the three to 50 ampere range are
generally satisfactory. No particular charge rate or time
can be specified for a battery due to the following factors:
1. The size, or electrical capacity in ampere-hours
(A.H.), of the battery.
Example: A completely discharged 70 A.H. battery
requires almost twice the recharging as a 40 A.H.
battery.
Fig. 5 b -V ie w Inside Vent Well
E L E C T R O L Y T E
AT C O R R E C T
LEV EL
E LE C T R O L Y T E
LE V EL T O O
LO W
10-30 CHEVROLET TRUCK SERVICE MANUAL