Thread: Dead Electrical
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Snuffy \Hub Cap\ McKinney Snuffy \Hub Cap\ McKinney is offline
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Default Dead Electrical

"Ralph Mowery" wrote in message ...

"Snuffy "Hub Cap" McKinney" Snuffy-Hub-Cap@Livebait-Before and after
cleaning all the connections in the starting circuit the voltage drop
during starting is about the same - less than 3V.

I meant to add that all the connections were tight but several had various
levels of corrosion. After cleaning the overall .resistance from pos or
neg battery post to starter or block block went from around 1.9 to 1.4
ohms. That's not enough to prevent starting, but I suspect that one of
the .connections was intermittent.


Chances are the 1.9 and 1.4 ohms are some meter error problems such as the
leads not making good connection to the points they are measuring.

As large and as short as the wires are you should have way less than one ohm
of resistance, even less than .1 of an ohm.

If you had 1.4 ohms of resistance before the starter, it would never turn.
The starter has less than .1 ohms of resistance. Almost all the voltage
would be dropped in that 1.4 ohms and none left for the starter. With just
1.2 ohms of resistance you could only have 10 amps of current for the
starter, hardly enough to make it spin.

As this is electronics repair, anyone on here should be able to apply basic
Ohms law to see this.


Yes, you're right. The zero was offset on the meter. Measuring again showed resistance is lower than the detectable value for this meter. Thanks.