Charging question

mf7lakes

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When engine is running, pax side battery shows it is receiving 14.4 volts when measured between the posts. Driver's side battery shows 12.8 volts. To me, that means there's a problem in the big red wire running from the pax side battery???
 

Clb

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Parasitic loss will account for a little bit of this.
But probably not 1.6 volts worth.
Are both leads solid and clean on the contact points on both batteries?
Both known good batteries?
Separate 1 lead at a time from both sides and meter it
 

mf7lakes

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Both batteries test very good, separately & with no leads attached -- leads are clean/solid -- well, I think if you separate the positive lead from pax side battery it definitely won't charge -- maybe I'm not understanding you.
 

Clb

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Testing to see if the wire has resistance...
If the internal resistance is high due to corruption of any sort, it wont flow power as well as a good clean one.

Disconnect from the batteries set vom( voltage, ohms, milliammeter) to ohms/Continuity touch leads together, verify that you have sub .o5 ish ohms,10 woud suco .00 would rock.
Then touch 1 to 1 end of cable, repeat on the other end.
Observe the reading.
Should be zero, the higher it is the worse the condition of the wire is.

Load testing is for battery health, a high currant load is applied and amps measured...
Testing voltage at rest and seeing 12-13v does not indicate a healthy battery.

Continuity is for wire health.
Test as above.
 

lotzagoodstuff

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Testing to see if the wire has resistance...
If the internal resistance is high due to corruption of any sort, it wont flow power as well as a good clean one.
If the batteries load test OK, I agree with Clb in that there's something going on inside the wire insulation. Good luck, wiring stuff is challenging.
 

Jesus Freak

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The original wires have a really cool way of looking just fine but having a ton of green corrosion inside the end of the wire right next to the lead clamp on the battery. It's absolutely amazingly fantastic to track down such things.

What I do is Cut the lead clamp off, crimp on a brass eyelet thingy and use the battery clamps that have bolts in them like for deep cycle batteries.

Have fun chasing your wires! That's almost as thrilling as a bad ground!
 

Jesus Freak

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Both batteries test very good, separately & with no leads attached -- leads are clean/solid -- well, I think if you separate the positive lead from pax side battery it definitely won't charge -- maybe I'm not understanding you.
There's no understanding electricity, it's still considered "theory", no one really knows what it is, we just hope it will consistently continue to do what it's done in the past........... except for Ben Franklin, but he had it coming....
 

mf7lakes

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Hmmm -- I'll get exact readings after 2nd cup but, amazingly for me, I did test ohms yesterday -- meter tested at zero ohms but red wire tested at 5 or 6 -- somewhere in there -- I'll check again -- nice to know somebody who knows "THINGS"
 

Jesus Freak

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Several guys make their own, but there is some place that has a legit prefab set. I can't remember who though.
 

nelstomlinson

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If you can measure the resistance of that red battery-to-battery cable, it's too high. I think that's what Clb was getting at. Our little 3-1/2 or 4-1/2 digit Ohm meters just can't measure micro Ohms, so if there is resistance you can measure, it's too much.
 

ihc1470

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Do a voltage drop test under load and it will tell you what is going on. Cheep drop test, put it under load for a few seconds such as cranking it over turn on headlights etc and then feel for a hot spot. Heat equals resistance and that will be your trouble spot.
 

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