xt7pzg6g4w7s https://exploreuk.uky.edu/dipstest/xt7pzg6g4w7s/data/mets.xml Kentucky. Department of Education. Kentucky Kentucky. Department of Education. 1949-03 bulletins English Frankford, Ky. : Dept. of Education This digital resource may be freely searched and displayed in accordance with U. S. copyright laws. Educational Bulletin (Frankfort, Ky.) Education -- Kentucky Educational Bulletin (Frankfort, Ky.), "Pupil Transportation Facts 1935-48: Suggestions for Safety, Comfort, and Efficient Operations", vol. XVII, no. 1, March 1949 text
volumes: illustrations 23-28 cm. call numbers 17-ED83 2 and L152 .B35. Educational Bulletin (Frankfort, Ky.), "Pupil Transportation Facts 1935-48: Suggestions for Safety, Comfort, and Efficient Operations", vol. XVII, no. 1, March 1949 1949 1949-03 2022 true xt7pzg6g4w7s section xt7pzg6g4w7s 0 Commonwealth of Kentucky 0

“EDUCATIONAL BULLETIN
g
PUPIL TRANSPORTATION

Facts 1935 - 48

Suggestions For

Safety, Comfort, and Efficient Operation

Published by
£21,, DEPARTMENT OF. EDUCATION

_ BOSWELL B. HODGKIN
Superintendent of Public Instruction .

ISSUED "'Mox'rl'iny

Entered as second-class matter March 21, 1933, at the post ofﬁce at
Frankfort, Kentucky; undef‘the Act of August 24, 1912.

Vol. XVII MARCH, 1949§E222§1i.—-Né:‘~f
324119 " **'>*:

FOREWORD

This publication contains suggestions for more efﬁcient opera-
tion of school buses and for providing more safety and comfort
for the children being transported. There is being presented, for
the ﬁrst time, suggestions for the erection of waiting stations for
pupils who have to walk some distance before they reach the bus
in the morning. During inclement weather this will make it possible
for the children, in case they have to wait a few minutes for the
arrival of the bus, to enter the bus without undue exposure.

Because the question is so often asked whether buses should
be publicly owned or privately owned, the latest information avail-
able for the department of education has been presented. The sug-
gestions for school bus maintenance are those that have proven
of value in those shops where boards of education are operating
their own buses.

Two tables on general information concerning operation of
school buses are presented. ' Their contents have been tabulated
from reports ﬁled with the department of education by county
school district boards of education. It may be noted that one table
contains facts for the ten-year period 1935-36 through 1945-46.
These facts are taken at the beginning, middle, and close of this
period. Another table containing information for 1947-48 is pre-
sented in a separate tabulation.‘ The facts contained therein are
for the operation of school buses under conditions which resulted
from World‘W‘ar Number Two Conditions under which these facts
are presented are not comparable to the facts contained in the
table for the ten~year period 1935- 36 through 1945- 46

I recommend for careful consideration this publication to

superintendents, boards of education, and citizens concerned s 1th
' the ever increasing problem of pupil transportation The informa-
tion contained herein was prepared by Mr. J. M. Dodson, Director
Pupil Transportation, State Department of Education.

BOSWELL B. HODGKIN,
Superintendent Public Instruction.

TABLE OF CONTENTS

Page
I. Introduction .............................................................................................. 894
>pera- II. Waiting Stations 895 '
mfort
1, for 4
Is for 111. Public vs. Private Ownership .............................................................. 897 .
e bus
sable IV. School Bus Maintenance ........................................................................ 899
tr the
Factors Related to Efficiency in School Bus Maintenance ........ 899 .
h - .
0“.” Purchasing Parts and Supplies ........................................................ 900
ava11~ ,
3 sug- Care of the Bus in Summer 901
roven
rating General Information on School Bus Maintenance .................... 902
on of V. Miscellaneous Information 1947-48 ................................................... 909
dated
ounty . .
t b1 VI. Miscellaneous Information 1935—36, 1940-41, 1945-46 .................... 913
a 6
45-46.
f this VII. Tables
3 pre- . .
11 are Number l—«Length of Term County District ................................ 926
ain‘t: Number 2—Annual Cost per Pupil Transported ...................... 926
ac
n the ‘ Number 3—Average Number Pupils per Bus ............................ 927
on to Number 4—Percent of Census Transported ................................ 928
. with
'orma Number 5-Percent of Current Expenses Used for
rector Transportation .............................................................. 928
Number 6—Cost in Cents per Bus Mile .................. 929
Number 7—Cost in Mills per Pupil Mile ...................................... 929
[1.
Number B—Number of Vehicles Operated: ...... j : ...... _.- 93‘)
Number 9—-Number or Pupils Transportedf.m_ ...... _. .i..:n~....s.:~_ 930

LIBRARY
UNIVERSITY OF KENTUCKY

I INTRODUCTION

The pupil transportation program in various counties through-
out the state has become one of the major phases of the education
program with which the school administrator has to deal.

Because pupil transportation has become such an important
factor in equalizing educational opportunities in the county school
districts of the state, the demand has exceeded the ability of many
boards of education to conduct properly a suitable program of trans-
portation. Its rapid growth has made it more necessary that school
administrators give more thought to planning the transportation
program in order that the best service can be obtained in the most
economical manner. Since most school boards must do the big task
of transporting the children in their districts on a limited amount
of money, it is becoming more and more important that they have
available more detailed facts than they now have. These facts
should be collected on particular phases and for a period of years.
This can best be done by a system of records and reports in order
that each individual may have comparable data with his neighbor.
Plans are now under way to improve and make more uniform the
present system of records and reports for the school transportation
program in the state.

It is becoming more apparent, yearly, that parents are not
satisﬁed with any type of a transportation program. They are more
'and more demanding that their children be transported safely and
comfortably. The board of education is faced with the problem of
doing this economically.

School buses are safer and more comfortable now than they
were a few years ago. The school bus driver is an important factor
1n both the safety and economical phase of school bus operation.

The following parts of this publication will give suggestions

_ for improving conditions in safety, comfort, and economy of the
school program which will be applicable to most of the school dis-
tricts of the state which operate a pupil transportation program.

. 1

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II WAITING STATIONS

With the view of improving the comfort of the children and the
safety and economy of operation, some of the boards of education
in the State have found it to be practical to erect along the bus
routes some small buildings commonly known as waiting stations.
These buildings will serve two purposes. First, they will eliminate
series of stops coming close together, as well as keep children from
exposure to inclement weather. Instead of a school bus making
several stops along a given distance, the children will assemble at
the waiting station; thereby saving considerable expense to the
board and time on making the daily route. In the second place,
it has been found that if the children who live on a side road have
a more comfortable place to wait on the main road, there Will be
less pressure for an extension of the bus route down this side road.

These buildings are usually constructed out of rough, inexpen—
sive material, with an extended roof in front so that the children
may watch for the bus without getting wet during rainy weather.
The posts are usually put into the ground deep enough to keep
the building from being overturned easily. They should not be
erected in places along the road where they might obscure the
vision of other motorists to the extent that they would not be able
to see clearly trafﬁc going in the opposite direction. Neither should
they be located in a place where it is dangerous for the school bus
to stop; such as on a bad curve, or just over the crest of a hill, etc.
They should not be placed in such locations that would cause undue
handicap to the school bus in getting started again.

The cut accompanying this discussion gives dimensions and
a suggested bill of material for the small waiting station. This is
large enough to shelter ten to ﬁfteen children. Blueprints are
available in the State Department of Education for use of super-
intendents who desire to construct buildings of this size. Blueprints
are also available for a larger size that will shelter twenty-ﬁve to
thirty children. Upon request, the State Department of Education
Will furnish blueprints for each size waiting station. '

895

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SCHOOL BUS WAITING STATION

DEPT OF EDUCATION FRANKFORTIK!

III

III PUBLIC OWNERSHIP VS. PRIVATE OWNERSHIP

Another experience of boards of education for safety and
economy of pupil transportation is that of public ownership and
operation of school buses. This change will eventually take place
in all school districts if the present trend continues. It must be
said, however, that public ownership is not a cure-all for the prob-
lems that are involved in pupil transportation. A poorly managed
program under school ownership can be more expensive and more
unsatisfactory than a well-managed program under the manage-
ment of an efﬁcient contractor. Public ownership places a greater
responsibility on the school administrator. He must purchase buses
and supplies, employ and supervise drivers, and operate a main-
tenance program.

Information available in the State Department of Education,
as well as experience of those in charge of school transportation
in other neighboring states, indicate that there are certain deﬁnite
advantages to school ownership over private ownership of school
buses. Some of these are as follows:

1. Many examples may be found where large school buses are
being operated over routes with unoccupied seats, while
smaller buses are operating in other sections of the district
with overcrowded conditions under a system of private
ownership. When buses are publicly owned, the larger buses
can be sent to those sections of the district where the
smaller overcrowded buses are being operated. This ex-
change has two advantages, economy of operation and
safety to the pupils being transported. Under private own-
ership such an exchange is practically impossible unless the
owner goes with the bus. If the buses are publicly owned,
it is a matter of changing buses. This change does not
aﬂt'ect the driver since the one operating the smaller bus
should be able to drive the larger bus as efﬁciently as he
does the smaller bus.

2. In public ownership boards of education operate buses with-
out any idea of proﬁt. They are exempt from paying certain
taxes which are required of private owners. They may
purchase supplies, equipment, repairs, etc., at wholesale
prices, while the private owner usually must pay retail.

897

. Public ownership usually provides a situation which makes
possible a more efﬁcient maintenance program. Experience
has usually shown that when boards of education operate
as many as ﬁfteen buses, they can afford to operate these
under a program of public ownership and can provide an
excellent maintenance program in a board operated garage.
It is sometimes found that this may be done with as few
as ten publicly owned buses when the mechanic serves as
a driver. Some are of the opinion that under a system of
contract operation of buses the owners will take better care
of the property than would be possible when buses are
publicly owned and operated. Experience in North Caro-
lina tends to disprove such belief. In that state the buses
are state owned but operated by school districts. The
mechanics are trained and imbued with the idea that it is
their primary job to prevent break-dowu by a preventive
maintenance before the bus must be taken off the road
because of need of repair. By such a program an inter—
ruption of service is prevented. It is of no interest to the
mechanic of publicly owned buses to have the buses come
for repairs. Their chief interest is to keep buses from
coming to the garage. This interest will result in a more
thorough inspection of the buses while they are in operation
and when they are being repaired. Not only will an efﬁcient
maintenance program under public ownership cost less, but
it Will provide more satisfactory service to the children
being transported.

. Information available from reports made by diﬁerent dis—
tricts for the school year 1947-48 disclose some interesting
facts in connection with private and public ownership of
school buses. Some of the items which appear to be of
most interest in this connection are:

a. Total current expense of operation was:
8.27% in districts where all buses are publicly owned
10.30% average for all of the districts in the state
12.04% in districts where all buses are privately owned
b._ The average cost per pupil transported was:
$19.21 per pupil in districts where all buses are publicly
owne
§21.10 per pupil which is the average for all of the districts
in the state
$26.37 per pupil in districts where all buses are privately
owned
c. Cost per bus mile was:
0.178 in districts where all buses are publicly owned
0.187 which is the average for all of the districts in the state
0.362 m districts where all buses are privately owned

898

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(1. Cost per pupil mile was:
.0020 in districts where all buses are publicly owned
.0025 which is the average for all of. the districts in the state
.0062 in districts where all buses are privately owned
It may be seen from the above that whether we consider the
percent of current expense of transportation, the cost per pupil
mile, the cost per bus mile, or the annual cost per pupil transported,
publicly operated buses were cheaper in Kentucky during the school
year 1947—48. The above facts were derived from reports made by
the school districts and ﬁled with the State Department of
Education.

IV SCHOOL BUS MAINTENANCE

Some Factors Related to Efﬁciency in School Bus Maintenance

It is desirable that boards of education keep publicly owned
buses to one or two makes insofar as is practical. This will be
economical since the greater the number of makes and models in
a school bus ﬂeet, the greater amount of money that must be
invested in parts and the more complicated the maintenance pro—
gram will become.

The bus should be large enough to do the job that is expected
of it. A chassis for a 36-passenger body cannot be expected to
carry the load of a AIS-passenger body through mud and snow
without excessive cost for maintenance. It is poor economy to
operate a school bus whichis too light to do the job required of it.

The success of a school bus maintenance program will depend,
to a large extent, upon the ability and training of the persons who
are responsible for the maintenance and operation of the buses.
The cooperative efforts of a number of individuals are required if
the maintenance program is to function in the highest possible
degree of efﬁciency. Each of these individuals should be capable
of carrying his part of the responsibility.

Another important factor in school bus maintenance is the care
of garage facilities and equipment used. Any individual who is
in charge of the school bus garage should have a knowledge of
what is really needed to make the program a success. It is usually
regarded as poor economy to attempt a school bus maintenance
program in quarters which are neither arranged nor equipped for
satisfactory work.

The operation of the maintenance program should follow a
deﬁnite procedure. Bus drivers should take the time to report

899

indications of trouble in order that many repair jobs can be pre-
vented. Bus inspection should be regular and follow a set pattern.
Preventive maintenance is one of the keys to lower transportation
costs. The work program in the garage should be well organized
in order that the maintenance program will obtain maximum
efﬁciency.

Purchasing Parts and Supplies

The purchase of parts and supplies is a complicated problem
when there are a number of makes of buses operated. It is usually
regarded as good practice to keep the stock of major parts to a
minimum if parts can be purchased as needed. This practice cuts
down the investment in parts, prevents unnecessary deterioration,
and simpliﬁes the problem of storage. A board of education which
operates a maintenance program must utilize efﬁcient business
procedure if it is to furnish transportation service at the lowest
possible cost. A district which operates a number of publicly
owned school buses should give consideration to the following
purchasing procedures:

1. The person responsible for the purchases should have
thorough knowledge of the parts and supplies used in the
operation and maintenance program. It may be possible to
buy more than one part that Will ﬁt into a given place.
Frequently the service of one of these parts will be more
satisfactory than that of another.

2. Deﬁnite speciﬁcations for the parts and supplies to be
purchased should be used. In many cases, speciﬁcations are
set up by the chassis manufacturer; but unless the buyer
is familiar with them, they are of little value. In other cases
the manufacturer may make no recommendation at all. In
that event it would be Wise for the purchaser to make up
a list of exact speciﬁcations to be used in buying parts and
supplies.

3. One of the chief objectives of the development of effective
purchase procedure is to obtain parts and supplies that
meet speciﬁcations at the lowest possible price. Quantity
purchases such as the year’s requirement for gasoline, oil,
and tires should be followed. This should be done through
bid procedures. When the board of education decides that
the quantity to be purchased is too small for bid procedures
they may agree with a dealer on discounts to be allowed
on parts or supplies.

900

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The purchasing of parts and supplies should be handled so
there will be a record of what has taken place. The request
for bids should be in writing and should state clearly the
speciﬁcations of the material to be purchased, the condition
of sale and delivery, and the plan of payment. When such
a procedure is followed, there should be no ground for
misunderstanding. Records will permit accurate budgeting,
accounting, and reporting.

In the payment of parts and supplies, bills should be in-
spected to see that they do not include taxes from which
the school district is exempt.

Care of the Bus in Summer

When buses are stored for the summer, it is recommended that
a plan be adopted whereby each bus would have the motor started
at least once in each two weeks and that the bus be driven a short
distance in order that lubricants may be recirculated to all moving

parts.

I11 school districts which ﬁnd it necessary for publicly owned
school buses to remain inactive for several weeks, thebuses should
be prepared for dead storage. The following are recommended

steps :

Remove the spark plugs and insert a small quantity of light oil
on the top of each piston.

Push down the clutch and insert a board of sufﬁcient thickness
under side of the floor board to hold the clutch in a slightly
released position.

. Drain the gasoline tank. If this is not practical, a gasoline tank

that is ﬁlled with gasoline will develop less moisture from
condensation than a partly ﬁlled tank.

Remove the gasoline line at the fuel pump and substitute a short
line that is submerged in light oil. Crank the motor and allow
it to operate until the gasoline in the fuel pump and carburetor
is exhausted and replaced by the light oil.

Drain the cooling system thoroughly, wash out, and ﬁll with
water to which a rust inhibitor has been added.

Remove the battery and store in a dry place, keeping charged
at intervals of at least four weeks in order to bring the speciﬁc
grav1ty of the electrolyte up to normal.

Inﬂate the tires to slightly more than the factory recommended
pressure.

Store tires in dark areas where they are less likely to
deteriorate.1

1Developing a. Transportation Program for Florida. Schools, Florida School
Bulletin, 9:26-28, April—May, 1947.

901

General Information on School Bus Maintenance

Most of the detailed procedures concerned with the maintenance
of a particular bus chassis should be based on the recommendations
of the chassis manufacturer. The manufacturer will have developed
these recommendations after long experience, research, and study;
and no user, particularly one operating on a small scale, is likely
to have sufﬁcient information to justify deviation from the recom-
mended practices. Therefore, the manuals and charts furnished by
the manufacturer should serve as the guide for the maintenance of
a particular chassis. Nevertheless, general procedures and practices
apply to almost any make of bus. Information and suggestions
related to some of these general procedures and practices are given
below.2

Cooling System

If either antifreeze solution or water, depending upon the
season, drains out rusty or rust or grease deposits are found in
the radiator, the cooling system should be cleaned. Should the use
of standard cooling system cleaning compounds prove ineifective
the system should then be reverse-ﬂushed. When preparing for,
and during the use of antifreeze solutions, oil hoses and connections
require particularly careful inspection for leaks.

Clean the dirt, insects, and other accumulations from the
exterior of the radiator core by blowing out with compressed air
or with a stream of water applied carefully from the rear side of
the core.

CAUTION: When straightening radiator cooling ﬁns, use only
a suitable shaped piece of wood or blunt instrument to avoid
puncturing tubes.3

Engine Oil Pressure

Too much emphasis cannot be made to the maintaining of
proper oil pressure in engines. Failure of the engine oiling system
can almost instantly cause serious damage to the bearings and even
to the crankshaft and needless destruction of these items may cause
indeﬁnite loss of use of the vehicle.

Permitting a vehicle to run with low oil pressure can cause
damage to the engine. Some of. the principal causes of low oil
pressure are:

1. Oil pump screen clogged.

2. Excessive crankshaft and connecting rod bearing clearance.
3. 011 pump worn excesswely.
2School Bus Maintenance, Glen E. Featherston, p. 32.
19“! Ereggntive Maintenance Program. Washington, D. 0., Navy Department,

902

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Drivers should be carefully instructed 011 the need for watch-
ing oil pressure.4

Engine Oil and Filters

Engine oil does not “wear out” in 1,000, 2,000, or 10,000 miles.
It does, however, become more or less rapidly contaminated with
the following materials:

1. Dirt drawn in through crankcase system or carburetor.
2. Unburned fuel, particularly due to choking in cold weather.

3. Water from combustion gases passing pistons and from air drawn
in through crankcase ventilating system.

4. Carbon and soot from combustion, especially during idling or
if the carburetor or ignition system is not performlng properly.

5. Lead compounds from burning gasoline sometimes cause the oil
to become gray or brown in color.

6. Metal particles from engine surfaces.
7. Products of oil oxidation or deterioration which may form
gummy or sticky deposits of “varnish” or sludge which tends to
clog oil lines and screens.- .

Because of these contaminants, some of which no ﬁlter can
eliminate, it is sound economy to replace the oil at regular inter-
vals. Under average conditions, where dust is not too great a
factor, the changing of oil at the monthly (1,000-mile) inspection
is recommended. The changing of oil at the monthly period is
advisable even when the mileage run is substantially less than
1,000 miles per month. In such cases the oil will often be par-
ticularly contaminated because of excessive idling and choking.

Certain of the engine oils now being produced contain addi—
tives and are generally known as “detergent” oils. Oils of this
type have the ability to keep ﬁnely divided materials dispersed and
prevent their forming sludge deposits. In addition, this quality
may exert a washing or ﬂushing action on existing engine deposits,
tending to gradually remove or take them into suspension. Should
this type of oil be put into excessively dirty engines clogging of
oil lines and pump screens may occur, causing bearings to burn
out soon after changing the oil. Caution should be exercised in
watching such engines. Several frequent changes of both oil and
ﬁlters should be made to insure the cleaning up of dirty engines.
Detergent type oils will discolor more rapidly than nonadditive oils
because of their holding material in suspension. .

Care should also be exercised in using the proper viscosity
(SAE No.) of oil in engines. The engine manufacturer’s recom—
mendations should be observed. I

‘ Ibid., p. 25.

903

The purpose of an oil ﬁlter is to remove all foreign solid
particles from the oil, thus giving better lubrication and longer
engine life. Since the efﬁciency of a ﬁlter depends entirely on its
ability to remove solids from the oil, the ﬁltering elements must be
changed at intervals. When the oil on the dipstick is dirty, the
ﬁlter element should be changed.5

Engine Operating Temperatures

Engines in vehicles used in short run or stop and start work
will often run cold almost continuously. Such a condition will
contribute to excessive fuel dilution and sludging with consequent
increased engine wear. This cold operation condition occurs not
only in the coldest weather, but also in cool weather and even in
warm weather, if the engine does not run sufﬁciently long to per-
mit the proper warming up. The use of high temperature range
thermostats is essential in this type of operation.5

Air Filters

The air cleaner is provided to keep road dust out of engine
and carburetor. This dust is loaded with minute particles of abrasive
which if permitted to enter the engine will cause rapid wear of
cylinder walls, pistons, and rings. Rapid engine wear necessitates
the use of more replacement parts and it also increases oil and
fuel consumption.

If the air cleaner is allowed to become clogged with dirt and
left in that condition, the ﬂow of air to the carburetor will be
restricted thus causing increased fuel consumption, engine heating
up, crankcase dilution, and otherwise prevent good engine per-
formance. Air ﬁlters must be cleaned and served at every monthly
maintenance period. Under severe dust conditions, the ﬁlter should
be cleaned more frequently.

There are two types of air cleaners in general use: the wire
gauze type and the oil bath heavy duty type. The oil bath ﬁlter
is the more efﬁcient type and is deﬁnitely recommended. The
manufacturer’s instruction manuals should be consulted for speciﬁc
information on the servicing of the ﬁlters.

Where crankcase ﬁller caps are equipped with gauze ﬁlters,

these caps should be washed in kerosene and reoiled with motor oil
at frequent intervals.6

Spark Plugs
Because 'of the differences in engine design (compression ratio,
range of engine speed, etc.) there are wide diﬂferences in operating

'Ibld., p. 25.
‘Ibid.. p. 26.

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temperatures within the combustion chambers of different makes
of engines. This variation in temperatures has necessitated the
design of spark plugs that will function in the individual makes
and types of engines. Spark plug manufacturers have available
Recommendation Charts which show the proper spark plugs and
their correct gap setting. The correct plug is the one which will
remain hot enough at low speeds to prevent fouling (building up
deposits which will short out the plug) and also remain cold enough
at high speeds to prevent preignition (ﬁring of the fuel prior to
spark discharge).

If the spark plug is not drawn down securely on a clean
gasket, the ﬂow of heat from the spark plug is restricted, thus
causing it to operate at a temperature higher than that for which
it was designed.6

Brakes

1. Cleaning of Drums, etc.

When operating vehicles under severe conditions of mud,
dust, or water, the cleaning of brake drums and shoes may be
necessary more frequently than at the semi-annual service
periods. Dirt or sand that is allowed to remain inside brake
drums acts as an abrasive, causing rapid wear of drums and
linings. Excessive moisture causes rapid corrosion of all moving
parts of the brake system.

2. Hydraulic Brake Fluid

Only standard types of hydraulic brake fluid should be used.
Substitute ﬂuids may have a severe action on rubber parts,
causing them to become sticky, preventing proper piston action,
or due to expansion of the rubber parts, cause them to lose
their sealing qualities. Other types of ﬂuid may cause vapor
lock, or, due to extreme thinness, leak past the rubber cups in
the Wheel cylinders and saturate the brake linings.“

Battery

The battery is an extremely critical unit in a motor vehicle.
Since it is the device for storing electrical energy, it controls the
starting of the engine, the entire ignition system, and all lighting.
It can be thought of as the heart of a motor vehicle. The principal
factors affecting battery life are:

1. Lack of Water

Water is lost as the result of charging and should be
replemshed as soon as the liquid level falls to the top of the
separators. If water is not replaced, and the plates become
exposed, the acid will reach a dangerously high concentration
that will char and disintegrate the wood separators, thus impair-
ing performance of the plates. Plates cannot take full part in
the battery action unless they are completely covered by the
electrolyte. Sulphuric acid need never be added to a cell unless
spillage has occurred.

' Ibid. . p. 26.

905

. Loose Hold—down

Hold-downs if not properly adjusted will allow the battery

to bounce in the cradle. This will not only crack battery cases

,but also do severe damage to the plates by causing the active
material in the grids to drop to the bottom of the battery.

. Overcharging
A high generator charging rate burns up the plates and
seperators; and the violent gassing action forces the active
material from the plates so that it collects in the bottom of the
cell and thus is lost.

. Undercharging
A battery operated with insufﬁcient charge over a long
period of time may develop a coating of the plates which will
permanently reduce the battery capacity. In addition, a partially
charged battery is liable to freeze during severe wmter weather.
The electrolyte of a battery in various stages of charge will
'start to freeze at temperatures indicated below:

Speciﬁc gravity Freezing