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You can extend your meter leads with just a plain piece of wire, just make sure you make good connection and check and record the resistance of the leads and extension before testing the cables
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Using a digital voltmeter observe the cranking voltage while hooking up the meter to the starter post and the starter frame - not the cable, but the threaded post on the starter.Originally posted by blackbear View Post
Again hook up your meter to the battery terminals, not the cables, and again record the voltage reading while cranking the motor.
If there is more than 1 volt difference between the two tests, then you have a cable or a connection problem that is causing a voltage drop.Comment
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a clarification for those that cant or wont use the forum search function.
what I am asking is the voltage drop on each cable/component.
means one lead on the actual battery positive TERMINAL,not cable, and the other lead on the starter main positive post, again NOT cable.
pull the stop lanyard.
crank the engine, if voltage reads more than .75v you have an issue.
do the same for the negative cable, between the battery POST and a clean engine block ground.
more than .5V and there is an issue.
on the positive cable if voltage drop is more than .75V then you can start backing up and find the component that is dropping the voltage.
remember voltage is a measure of electrical pressure NOT electron flow.
think of ye ole garden hose.
average house PRESSURE is about 50 PSI.
layout the hose, turn on the spigot leave the sprayer nozzle closed.
we now have 50 PSI in the hose.
turn off the spigot.
we still have 50 PSI in the hose.
now open the nozzle, pressure just rapidly reduced and there is little FLOW.
electron FLOW measured in amps is what makes the wheels go round.
remember in a circuit as resistance increases so does the voltage dropped and FLOW ,amps, decreases.
think of the above spigot as a variable resistor.Comment
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