Battery Terminal Melted (1 Viewer)

[MyLoCoLife]

Hi. Just got this 96 last week. So this happened today when I started the truck. Last weekend I had the battery disconnected to take the interior apart to clean. I did not notice anything odd. I even cleaned the terminal and post putting it back on. I drove it this week running errands with no issues starting. Any thoughts would be helpful. I am hoping it was just a cracked terminal. Carfax was sparse on info and it is a rough example on the outside. I know it will need some work mechanically like Birfields possibly (no Noise yet) and Axle seals. 213000 miles on engine and feels strong and stable. I bought it rough precisely because I need to learn to drive it here in Colorado's mountains and I expect to make more than one mistake trying stupid things. That's my story. I hope to learn a lot more from you guys.

 

[BILT4ME]

First thing I see is that there are no fusible links installed there.

Those should be installed to prevent exactly what you are experiencing.

You have some troubleshooting to do.

Look for melted wires in the harness by the EGR, and in the harness above the glove box. Those are two of the first places with issues.

Also check your starter and ground cables.

That shold NOT happen.

Maybe go to Mil-Spec battery cables instead of the clamp-on like you have.

https://www.amazon.com/gp/product/B00X36RILW/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B003X51S00/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

 

[Dimples]

Wow, I'd check the cable down to the starter for shorts to ground before hooking that back up. That amount of melted lead took a significant amount of power to produce.

 

[midfat]

 

[BILT4ME]

May also check your starter. The contacts inside there may have fused and causing a direct short now.

 

[MyLoCoLife]

BILT4ME, fusible links are on the positive side. Is that wrong? I am Not hooking the new battery up until i can dig in and find a problem. Thanks for the tips.

 

[BILT4ME]

BILT4ME, fusible links are on the positive side. Is that wrong? I am Not hooking the new battery up until i can dig in and find a problem. Thanks for the tips.

Sorry, yeah that's correct. And they are still intact?

Having a Ground cable melt like that is VERY concerning. That tells me that you have a heavy short somewhere outside the fusible side of things. Lucky it didn't burn to the ground. Otherwise, it COULD be a VERY loose ground cable during starting...... I've never seen one melt like that though.

Check your fuse block and especially the starter.

 

[george_tlc]

That level of short circuit must be on the starter lead/starter motor. That's the only THICK gauge cable that could carry enough amps to melt the battery terminal versus the cable itself.

I'd inspect the entire cable run from the battery+ all the way to the starter. My guess is that you have a massive short in the starter since current would only flow when you turn the ignition switch to start. Possibly the brush/commutator assembly has completely failed. Get enough amps flowing to a shorted starter (the motor assy) and the solenoid contacts will weld and not release when you release the ignition key. Then you just have huge current flow until something melts. I'd call yourself lucky that the entire damage is a melted battery terminal, versus exploded battery or a fire...

I would be replacing the battery+ cable (that goes to the starter) and also the ground cables (that goes to the block and the one that goes to the body), I'd imagine the insulation has been compromised at this point. Pull the starter and open up the motor and inspect the commutator and brushes. Check the solenoid contacts. If anything is suspect I'd replace the starter with a denso reman.

cheers,
george.

 

[MyLoCoLife]

Ya me neither. This scared the $!!+ out of me, the wife and dog. We bailed out when we heard the crackling! I Popped the hood as soon as i heard it and grabbed my insulated plyers to seperate the lead as it was still sitting in the puddle of lead. Snipped the small ground to the fender and then took a breath. I'm so glad this was in may garage 5ft from my tools.

 

[MyLoCoLife]

That level of short circuit must be on the starter lead/starter motor. That's the only THICK gauge cable that could carry enough amps to melt the battery terminal versus the cable itself.

I'd inspect the entire cable run from the battery+ all the way to the starter. My guess is that you have a massive short in the starter since current would only flow when you turn the ignition switch to start. Possibly the brush/commutator assembly has completely failed. Get enough amps flowing to a shorted starter (the motor assy) and the solenoid contacts will weld and not release when you release the ignition key. Then you just have huge current flow until something melts. I'd call yourself lucky that the entire damage is a melted battery terminal, versus exploded battery or a fire...

I would be replacing the battery+ cable (that goes to the starter) and also the ground cables (that goes to the block and the one that goes to the body), I'd imagine the insulation has been compromised at this point. Pull the starter and open up the motor and inspect the commutator and brushes. Check the solenoid contacts. If anything is suspect I'd replace the starter with a denso reman.

cheers,
george.

My thoughts are the same about Starter problems.
I probably would have cheaped out and crossed my fingers about replacing the battery cables but since you said it, and I know better, I will.

 

[inkpot]

I would look everything over good but I am betting on a cracked/failed battery clamp.

 

[Tools R Us]

I would look everything over good but I am betting on a cracked/failed battery clamp.

Yep, plausible, if it happened when when the starter was engaged, there is a big amp draw, a compromised terminal can fuse.

 

[mudgudgeon]

Yep, plausible, if it happened when when the starter was engaged, there is a big amp draw, a compromised terminal can fuse.

Could be. If it was loose, the current could arc between the battery post and the terminal clamp.
Could explain the popping sound

 

[MyLoCoLife]

I would look everything over good but I am betting on a cracked/failed battery clamp.

I know the clamp was tight and the 2 small clamping bolts holding the wires to the terminal had a few more turns to them when i put it back on. I didn't inspect the clamp for a crack specifically. I will let you know what i find.

 

[inkpot]

I know the clamp was tight and the 2 small clamping bolts holding the wires to the terminal had a few more turns to them when i put it back on. I didn't inspect the clamp for a crack specifically. I will let you know what i find.

I’m thinking there was a crack in the neck area between the post clamp and the wiring clamp. If that crack grew until there was very little metal there to transfer current from the cable to the post, it may of created enuff resistance that the resulting heat melted the cracked area. I have seen both clamps and posts melt away from unexpected minimal connections from wiring to battery.

 

[nukegoat]

Like a little welder right under your hood. Neat

 

[brockdeck]

Like a little welder right under your hood. Neat

OBW (On Board Welding) for your overland adventure

 

[PDoyle]

does your top post hit your hood when it is closed?

 

[MyLoCoLife]

Just following up to all the replies.
What I found:
Starter was janky, lower bolt hole on starter was cracked but still holding, the plate that covered the contacts in the starter was missing a small bolt and one contact was replaced but the other was well worn. The round copper disk on the plunger had a bend in it and you could tell there was some welding going on.
The wires to the starter looks like someone knew about the solenoid bypass. It looked like a small Bosch type not the bigger ford solenoid. The wires to and from the solenoid are taped and I did not want to get into the Ford relay fix this time. I found the Black\Red stripe wire and it was a poorly soldered twisted wires tape job. I fixed that with a strong butt end connector and heatshrink.
The reman Toyota starter has a special connector that has no mate on the wire to it. For now I crimped on a female connector and stuck it in but I need to know what that connector is and get it on there. Battery cables were in good order, old, but visually ok. No Grounds or burnt spots. The +/- connections to the starter and ground to block were tight. I replaced them with the Recommended Mil style clamps, tinned copper lugs and 2/0 Welding Cable. New 8 gauge battery body ground.
New Battery
Removed, Cleaned and reinstalled Battery box, Wire wheeled old rusty battery box bolts, Cleaned under battery box area, Wire wheeled battery hold down hardware and repainted with Black PlastiDip. All electric connections received Dielectric grease.
Started right up the first try.
Thanks everyone.

 

[PDoyle]

Life is good