Worth mentioning - Hidden failures of wires that connect to batteries

[Reworked LMTV]

My apologies. I forgot to mention that I recently discovered occult damage to battery and power cables on my truck. I mentioned it in a thread, but some may not see it. I bet there are a lot of trucks out there with low voltage at the dash and throughout the truck. Anyway, I cut one of the larger wires coming in to the battery box to replace the connector. While the connector still looked "ok" with a bit of brushing, I decided to replace it for good measure. I'm glad I did. Cutting along the longitude of the cable, I discovered that the wire was devoid of all nickle, silver, zinc whatever, leaving a very dull corroded wire crimped in the connector. Likely water wicking or electrolysis or both. No doubt this was not a good electrical connection, likely causing a voltage drop / increased resistance. Problem is, you can't see it, it's in the crimp. If your truck is from the 90's, consider replacing all of the wires in the battery box. There probably is a S.T.O.P. on these wires with an expiration date, but I would not assume that if it looks good, that it is good.

 

[frank8003]

Thanks for posting this.
Exact same thing happened to GM cars in the 60's. It would sometimes make an intermittent, battery tied down good, but a big pothole or something and it would drive the alternator nuts, leading to replacement, then another, then another. Battery positive lead looked factory new, but POS.

 

[Ronmar]

The way to look for this without cutting apart the connections is to apply a load thru the cables and look for the hotspots. Resistance = heat and a good connection/connector installation should be no hotter than the adjacent cable. you can use a battery load tester for this, disconnect the cables at the alternator and apply a load there(I believe those cables are rated to 200A) then look at connections and cables with IR or thermograph... Many of these cables may use uncoated copper strands. They may be tinned at the ends where they were crimped or soldered. Bare copper may have discolor back under the sheath over time, but may still function just fine as long as the corrosion has not removed any material that reduces the individual strand gauge. That is the metal protecting itself and although it is dark, there is still copper under that layer of oxide. if the ends are tinned/plated and or connections soldered there should be an oxide free pathway thru the core of each conductor from connector to connector. Signs of severe corrosion are often distorted insulation and brittle inflexible cable, and of course hotspots when placed under load

 

[Reworked LMTV]

No, no, and no. IR yes.

The wires are full length silver coated. This is done to prevent oxidation of the copper. Once the silver is gone, oxides form and reduce conductivity greatly. None of the wires in the box are bare copper. Not a single connection was soldered. They were all crimped. Solder is not used, because it can melt under load. Welding, on the other hand is done. A bundle of wire with oxides between them is a bundle of electricity that is greatly hindered. You are assuming that the tips of the wire touch the connector. They do not, in a number of the battery box connectors. Reduced number of strand carrying high amps would definitely show up on IR.

The way to look for this without cutting apart the connections is to apply a load thru the cables and look for the hotspots. Resistance = heat and a good connection/connector installation should be no hotter than the adjacent cable. you can use a battery load tester for this, disconnect the cables at the alternator and apply a load there(I believe those cables are rated to 200A) then look at connections and cables with IR or thermograph... Many of these cables may use uncoated copper strands. They may be tinned at the ends where they were crimped or soldered. Bare copper may have discolor back under the sheath over time, but may still function just fine as long as the corrosion has not removed any material that reduces the individual strand gauge. That is the metal protecting itself and although it is dark, there is still copper under that layer of oxide. if the ends are tinned/plated and or connections soldered there should be an oxide free pathway thru the core of each conductor from connector to connector. Signs of severe corrosion are often distorted insulation and brittle inflexible cable, and of course hotspots when placed under load

 

[Ronmar]

Didn't assume anything, just going by personal experience with power systems. Mine do not appear to be silver plated, but are crimped. You know silver oxide is black right? No issue with soldered connections, and in a properly soldered connection, the tips of the wire DO touch the connector Quite frankly if a connection is running hot enough to melt solder, you have a serious problem or are severely under-engineered and are headed for heartbreak somewhere else...

 

[Swamp Donkey]

Solder is not used, because it can melt under load.

No, no and no....

 

[fuzzytoaster]

My apologies. I forgot to mention that I recently discovered occult damage to battery and power cables on my truck. I mentioned it in a thread, but some may not see it. I bet there are a lot of trucks out there with low voltage at the dash and throughout the truck. Anyway, I cut one of the larger wires coming in to the battery box to replace the connector. While the connector still looked "ok" with a bit of brushing, I decided to replace it for good measure. I'm glad I did. Cutting along the longitude of the cable, I discovered that the wire was devoid of all nickle, silver, zinc whatever, leaving a very dull corroded wire crimped in the connector. Likely water wicking or electrolysis or both. No doubt this was not a good electrical connection, likely causing a voltage drop / increased resistance. Problem is, you can't see it, it's in the crimp. If your truck is from the 90's, consider replacing all of the wires in the battery box. There probably is a S.T.O.P. on these wires with an expiration date, but I would not assume that if it looks good, that it is good.

Was the outer rubber cracked or showing some indication of how the water got in? Any spots in particular that showed the issue internally (at bend or something)? I have a few trucks with various low voltage issues so this intrigues me. One is an 08' so I hope the cable hasn't "expired" in that time frame.

 

[Reworked LMTV]

Lol yes silver oxide. My replacement connectors are closed and the wire do touch the tip, but a number of the military ones do not. I will see if I can find one for a picture. I will concede that soldered battery connectors can be used, assuming the correct solder and flux. Most are built in now to the fitting.


https://www.powerandsignal.com/Images/PDFs/Catalog_Full_Line__English_Connectors.pdf
<br>

Didn't assume anything, just going by personal experience with power systems. Mine do not appear to be silver plated, but are crimped. You know silver oxide is black right? No issue with soldered connections, and in a properly soldered connection, the tips of the wire DO touch the connector<img src="/images/smilies/icon_smile.gif" border="0" alt="" title="Smile" smilieid="1" class="inlineimg"> Quite frankly if a connection is running hot enough to melt solder, you have a serious problem or are severely under-engineered and are headed for heartbreak somewhere else...

 

[Reworked LMTV]

Actually the newer solder connectors are pretty impressive. Might have to try them.

No, no and no....

 

[frank8003]

Lol yes silver oxide. My replacement connectors are closed and the wire do touch the tip, but a number of the military ones do not. ~/~
https://www.powerandsignal.com/Images/PDFs/Catalog_Full_Line__English_Connectors.pdf
<br>

Thanks, am making the Chevy VOLT to power up the refrigerator, can use parts from that catalog.