Chevrolet 10 1971 Series, Chassis Service Manual

Page: 252 / 466

ENGINE-ELECTRICAL 6Y-2
ampere hour battery, (e.g. 3 amperes X 20 hours =60.
A.H.). A PWR (Peak Watt Rating) has been developed
as a measure of the Energizer's cold cranking ability.
The numerical rating is embossed on each case at the
base of the Energizer. This value is determined by
multiplying the max. current by the max. voltage. The
PWR should not be confused with the ampere hour rating
since two batteries with the same ampere hour rating
can have quite different watt ratings. For battery re­
placement, a unit of a least equal power rating must be
selected.
PERIODIC SERVICING
C O M M O N CAUSES OF FAILURE
Since the Battery is a perishable item which requires
periodic servicing, a good maintenance program will
insure the longest possible lift. If the unit tests good but
fails to perform satisfactorily in service for no apparent
reason, the following are some of the more important
factors that may point to the cause of the trouble.
1. Vehicle accessories inadvertently left on overnight
to cause a discharged condition.
2. Slow speed driving of short duration, to cause an
undercharged condition.
3. A vehicle electrical load exceeding the generator
capacity.
4. Defect in the charging system such as high resis­
tance, slipping fan belt, faulty generator or voltage
regulator.
5. Battery abuse, including failure to keep the Battery
top clean, cable ends clean and tight, and improper
addition of water to the cells.
LEVEL INDICATOR
The Battery features an electrolyte level indicator,
which is a specially designed vent plug with a transparent
rod extending through the center (fig. 3b). When the
electrolyte is at the proper level, the lopwer tip of the
rod is immersed, and the exposed top of the rod will
appear very dark; when the level falls below the tip of the
rod, the top will glow.
The Indicator reveals at a glance if water is needed,
without the necessity of removing the vent plugs (fig. 4b).
The Level Indicator is used in only on cell (second
cell cap from positive terminal) because when the elec­
trolyte level is low in one cell, it is normally low in all
cells. Thus when the Indicator shows water is needed,
check the level in all six cells.
An alternate method of checking the electrolyte level
is to remove the vent plug and visually observe the elec­
trolyte level in the vent well. The bottom of the vent well
features a split vent which will cause the surface of the
electrolyte to appear distorted when it makes contact.
The electrolyte level is correct when the distortion first
appears at the bottom of the split vent (fig. 5b).
ELECTROLYTE LEVEL
The electrolyte level in the Battery should be checked
regularly. In hot weather, particularly during trip driv­
ing, checking should be more frequent because of more
Fig. 2b-Internal V ie w of C ells Fig. 3b-Electrolyte at Proper Level
10-30 CHEVROLET TRUCK SERVICE MANUAL