cranking system and testing service Flashcards
what should you before removing the starter
determine if the starter is actually faulty
what should be the first thing tested when trouble shooting
the battery group
how can batteries be more accurately tested
disconnected from each other
when testing batteries with studs or threaded holes
use adaptors to connect the test equipment to
if a battery has a hydrometer eye
green = 75% or above charge dark = less than 75% should be charged clear = replace battery
how should you charge a battery if the hydrometer eye is dark
at a rate of 15-25 amps for 15 min
how can you remove a surface charge from a battery with a carbon pile
by placing a 300 amp load for 15 sec and waiting one minute
how is a battery load or capacity test preformed
draw 1/2 the battery amps for 15 seconds and take a voltage reading quickly from the batteries loaded terminal and compare to a chart
what should not be over tight on the battery
the hold downs because they can distort the battery case
how can you mix the water and electrolyte after adding it to a battery
by charging it with 15-25 amps for 15 min
what is used to check specific gravity of a battery
hydrometer or refractometer
what should specific gravity readings from each cell be within to be balanced
.050 points
what should the specific gravity of a charged battery be
1.265 to 1.280 S.G
what dose a blue haze in a battery cell mean
that it has been shorted and needs to be replaced
how do you check voltage drops on battery cables without a carbon pile
by checking each section while the starter is cranking the engine
high current and low speed usually means
a mechanical resistance
can be from the engine or internally in the starter
low current and low speed can indicate
high electrical resistance
normally caused by loose or corroded connections
higher than normal current draw on the starter will cause the voltage drops to be
higher
lower than normal current draw on the starter will cause the voltage drops to be
appear normal
to test the solenoid contact condition
connect a voltmeter to the motor and battery terminals
what is the total allowable voltage drop on a solenoid
.2 volts
when the starter motor is cranking the engine battery voltage should not drop below
- 6 volts for a 12 volt system
19. 2 volts for a 24 volt system
what is the total voltage drop allowable for the cranking system
.7 volts ( .5 for the cables and .2 for the solenoid )
when using a carbon pile to test for voltage drops how much current should you draw through while testing
500 amps for a 12 volt system
250 amps for a 24 volt system
make sure not to test longer than 10 seconds
