Battery cable

[CNYRVer]

Hi there everyone,
Well I went out to the barn where my RV is stored to start it up and while turning it over for like less than 30 seconds it died. I went out and checked the battery and the negative cable end had gotten so hot it melted the wire right off of it. Now the cable end is not the regular one that was on it from the factory, it's the kind where you strip off the insulation, slide it under the bracket and crimp it down. Any reason why this would have gotten so HOT !!! Its been extremely cold hear in upstate NY so I've had the battery on the charger probably longer than I should have, could this have been the reason??? Is it possible to over charge a battery?

[Bumps]

It was prolly a loose connection to the battery post or to the after-market connection at the post. If not a clean, tight connection, it will arc while under load and create heat. Sometimes it looks like a good connection to the naked eye, so it's always best to touch all of those connections every-once-in-a-while just to make sure they are absolutley solid. Keep them clean and tight ... no movement on the battery posts allowed. \ken

[FIRE UP]

Originally Posted by CNYRVer

Hi there everyone,
Well I went out to the barn where my RV is stored to start it up and while turning it over for like less than 30 seconds it died. I went out and checked the battery and the negative cable end had gotten so hot it melted the wire right off of it. Now the cable end is not the regular one that was on it from the factory, it's the kind where you strip off the insulation, slide it under the bracket and crimp it down. Any reason why this would have gotten so HOT !!! Its been extremely cold hear in upstate NY so I've had the battery on the charger probably longer than I should have, could this have been the reason??? Is it possible to over charge a battery?

Typically, "heat" is caused by resistance. Resistance is normally because of poor connections, but not always. Those "clamp" style battery cable ends are not the best means of conveying those heavy demand amps that the starter is calling for. Second, it's possible that, you may have a battery cable or, series of cables that have, for some odd reason, been replaced and, they maybe are too small for that kind of amp draw. Thus, the heat.

And, by the way, why the "long" cranking? Most of todays engines start, fairly quickly, due to fuel injection operational characteristics and more efficient systems all together. Or, is this a carbureted unit?
Scott

[CNYRVer]

Hi fire up,
It has a bad fuel pump and was trying to get it going. So is this cable going directly to the starter or does it go elsewhere? I may just but a new one instead of trying a new end.

[DIYRVGuy]

Yes, batteries can be overcharged. Check the water level.

Battery cable melting may have been partially caused by the poor battery connection and long cranking on the starter.

May also be a sign of a starter drawing more amps than normal.

Another consideration is the size of the battery cable. Are both cables the same size and are they decent size?

[FIRE UP]

Originally Posted by CNYRVer

Hi fire up,
It has a bad fuel pump and was trying to get it going. So is this cable going directly to the starter or does it go elsewhere? I may just but a new one instead of trying a new end.

CNYRVer,
Well Sir, you don't see what kind of make/model/year/ RV you have or, what engine. On most gas and diesel units, the main battery positive battery cable will go directly to the solenoid on the starter, not all, but most. But, on some coaches there may be auxiliary starter relays, solenoids, etc. that may be involved, depending on whether or not it's a diesel or gas coach, engine size and a few other variables.

So many people look at the battery cables on the batteries and, don't take into account the OTHER ENDS. The ground cables have one of the dirtiest jobs on the planet, hooked into the frame and other parts, under that coach which, sees ugly road conditions, wet, snow, slush, rust, corrosion etc. So, it pays to dig around, find those cable ends and, make sure that they're clean, free of rust and corrosion and, are making the best contact they can. And that also includes positive ones too. Good luck.
Scott

[MT4Runner]

Originally Posted by CNYRVer

So is this cable going directly to the starter or does it go elsewhere? I may just but a new one instead of trying a new end.

Best bet is to crawl underneath and pull the old cable off. It probably goes directly to the starter, but the best way to find out is to remove the old one. Use it to get the new cable made. Many battery shops can build a new cable with you, and with a commercial/industrial crimper can get a TIGHT connection that shouldn't loosen or allow corrosion. Also get the new ends shrink-wrapped to keep water out and prevent corrosion.

Excellent advice from FIRE up about checking the ground cable as well.

I had poor charging in my coach batteries due to a nearly absent ground path (was grounded through the subfloor of the coach with zero cable path).

[CNYRVer]

Thanks for all the advice guys and for those that are wondering I have a 1992 27ft Gulfstream Ultra Limited with a big old 7.5 L ford powering it.

[MT4Runner]

'92 29' Four Winds here.
Same 460 Ford with only 31,000mi on the ticker!

[CNYRVer]

Hi guys & gals,
well I got up underneath the RV and it's the original battery. From what I can see it is incased in that ribbed type wire cover and there's a bunch of other wires in their as well, I opened it up a little and the wires are taped together than once in the plastic covering its taped again by what looks to be about 200 yards of electrical tape!!! I can even see where it goes to underneath the rig. Since 'm not going to be able to just pull the old cable out, I think I'm going to put a "compression style" battery end on this cable so that I can get to the garage and look at it.

[wa8yxm]

Well Tarnation.. Or rather tarnish.

The wire and the clamp on replacement end are not the same metal, over time there is a reaction and they tarnish/corrode, whatever you wish to cause it,, This leads to RESISTANCE.

now, you are pulling oh, say 100 amps through that connector, when you start the engine,, Let's say there is .01 ohms,,, I^2 is 10,000 times R is back to 100 watts. That is a lot of heat for such a small sink.

[MT4Runner]

Originally Posted by wa8yxm

Well Tarnation.. Or rather tarnish.

The wire and the clamp on replacement end are not the same metal, over time there is a reaction and they tarnish/corrode, whatever you wish to cause it,, This leads to RESISTANCE.

now, you are pulling oh, say 100 amps through that connector, when you start the engine,, Let's say there is .01 ohms,,, I^2 is 10,000 times R is back to 100 watts. That is a lot of heat for such a small sink.

What do you think about soldering the crimped connection to keep oxidation out and get a great electrical connection?

73
KF7EFX

[FIRE UP]

Originally Posted by MT4Runner

What do you think about soldering the crimped connection to keep oxidation out and get a great electrical connection?

73
KF7EFX

When I built all the new inter-connecting cables for my 12V to 6V change-over, I did solder all the 1GA cable into the ends of the copper lugs. It was a bit tricky. Trying to heat up the ends of the cables, without damaging the ends of the insulation, was tactical. But I did it and, at this point, I'm not sure it's really any better than, utilizing a high quality crimping tool with properly prepared cable ends. Then, when the crimp job is done, you apply shrink tubing that incorporates a sealant when heated. I've done it that way too.

All of our Fire trucks batteries were crimped connected. The head technician utilized a "Copper" based anti-seize as conductive vehicle/sealant for the crimp. Those type of connections never gave us any trouble in over 100 fire trucks.
Scott

[twinboat]

Put one of the temporary ones on, like you had and find a truck repair shop, that will crimp on a replacement battery terminal.
Hopefully, you have enough cable left, to do it.

Good luck