Alternator batt post red hot

Ive concluded its not worth the risk of trying to use this alt. But I will say that even with the overheated connection, it was still charging. I could see that on my dash gauge. But the heat did some damage to the plastic piece at the batt post on the internal part of the alt. I'll just spend another $100 and get a new alt, and fix all the wiring. Heres some other pictures that maybe you have comments on.

Connections at fuse block look good

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Connections at solenoid look good


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Toasted crimp that was at the back of the alternator. The cable literally crumbled and broke off when I touched it.


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More pics coming
 
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I cant remember where I got the 4g cable. It appears to be audio style cable. The type with a bazillion fine strands. Could this have contributes to the problem? It is 4g cable

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See that? 1568 strands! Thats some fine wires huh?


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Here is the cable end showing the fine strands. That burnt end just crumbled and fell off when I touched it.

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Heres the melted internal component that convinces me to ditch this alt and get a new one.

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The fine strand wire isn't a problem as long as the crimp is good and there no oil or coolant leaks in the same area.
I have seen oil get in the fine stand wire where it was crimped and cause problems.

If you had any doubts, heat the wire with a propane torch and tin it real good with electrical grade solder before you crimp on the end lug. Or solder the lug on and then you don't have to worry about it.
 
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Time to choose what alternator to buy. Any opinions? This one I’m replacing was bought new. It’s a TYC brand. What are the best units for reliability?
 
I think I’m gonna go with regular 4 gauge battery cable for the alt + wire. And since my alt is located low because of vortec, my idea is to run the cable under along the stabilizer bar and up across the drivers shock tower. The current cable runs up the passenger side and across the top of the rad support. The new underneath route can trim about 2 feet from the cable length. I also got a 125amp mega fuse. I don’t know why LMR sent a 200 in the previous kit.

Shorter cable is better right?

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Be careful with that. The sway bar moves ( I'm sure you didn't mean the actual sway bar ). I ran mine along the top of the rack and pinion over and up by the drivers strut tower. Also, its a good idea to run another battery cable from one of the bolts on the drivers side front of the engine to the sway bar mount on drivers side. Can never have too many grounds. I mounted mine to the stud that the power steering pump bolts on with.
 
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I would never trust that alternator again

I’ve got another one on the way. I’m still not sure if it was a bad connection or an alternator issue. I need to replace the burnt wiring, alternator and check all accessories for amp draw just to make sure there’s nothing else contributing to the problem.
 
Be careful with that. The sway bar moves ( I'm sure you didn't mean the actual sway bar ). I ran mine along the top of the rack and pinion over and up by the drivers strut tower. Also, its a good idea to run another battery cable from one of the bolts on the drivers side front of the engine to the sway bar mount on drivers side. Can never have too many grounds. I mounted mine to the stud that the power steering pump bolts on with.

10-4. I’ll secure to rack instead of stabilizer. Good advice on additional ground cable.
 
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I think I’m gonna go with regular 4 gauge battery cable for the alt + wire. And since my alt is located low because of vortec, my idea is to run the cable under along the stabilizer bar and up across the drivers shock tower. The current cable runs up the passenger side and across the top of the rad support. The new underneath route can trim about 2 feet from the cable length. I also got a 125amp mega fuse. I don’t know why LMR sent a 200 in the previous kit.

Shorter cable is better right?
125, 150, 200 mega fuse are all okay. If you get a dead short, any one of them will blow before the battery cable burns up & starts a fire.
Yes, shorter DC cable is always best. 4AWG battery cable is perfect.
 
125, 150, 200 mega fuse are all okay. If you get a dead short, any one of them will blow before the battery cable burns up & starts a fire.
Yes, shorter DC cable is always best. 4AWG battery cable is perfect.

All these high current fuses are time delay and will carry an overcurrent for 5 -30 seconds or more according to the fuse specs. The best bet is keep the fuse as close to the rated current capacity as possible so that the time delay doesn't cause the fuse to blow after the damage has been done. A 200 amp fuse rated at 135% overload will blow at 270 amps in a time range of 120 seconds to 1800 seconds maximum. That's long enough to do some serious damage to the wire and other wires next to it. Remember that this is a 4 gauge wire rated for 120 amps and it probably doesn't have the105° C insulation temperature rating that is the standard for automotive wiring in the engine compartment.


See http://www.littelfuse.com/~/media/a...bolt-down-fuses/littelfuse_mega_datasheet.pdf for the fuse specs

See https://www.wirebarn.com/Wire-Calculator-_ep_41.html for automotive wire current specs.

@Blown88GT are you really a retired Electrical Engineer or am I mistaken about that?
 
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When I started looking for the starter cable for mine (I know it's larger than what you are using, read on) I spoke to a stereo installation shop about the cable they use and he said that fine strand stereo cable will take all the power you would need but the connections are very important, they use connections that are held with screws that capture the wire, they are very hard to solder for a good connection and the stuff I was looking at was like $7 a foot! He does not recommend soldering or for use as automotive starter cable, the covering is not good in high heat areas.
 
I’m leaning towards alt failure causing the over heating at the post. The 4g cable acted as a heat sink and that’s why it was scorched for 3” up the cable. The two factory #10’s were a little scorched too but nowhere near as far or as bad as the 4g, in my opinion simply because they’re smaller and did not soak up as much heat as the 4g did.

I see where the two 10’a go together at the fuseable link near the alternator. There also appears to be another fuseable link over by the solenoid. At that link there’s an orange wire connected to that fuseable link as well. Where does it go? When I omit using the factory batt wire from alt, can I also unhook it at the solenoid? I’m worried that unhooking the fact batt wire from the solenoid will take power away from this orange wire, which I don’t know what it feeds. Anyone know?

I relocated my fuse block for the batt wire. It previously was up top by the battery. Now it’s down on the frame rail near the power steering pump. It actually uses the steering line support bracket hole as a sturdy mount. I measured the old cable and compared the length reduction the new route will give. The new cable will be literally 4 feet shorter.

Below are 4 pics. Two of factory fuse link near solenoid showing the orange wire I’m concerned about disconnecting, and two of the new fuse block location.

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That orange wire should run to the voltsge sense wire at the alternator "D" connector yellow / white wire. I'm not 100% sure. Technically that wire should be yellow with a yellow stripe or yellow.

The way to treat would be to disconnect the black / orange whites along with the orange wire. Great for voltsge at the yellow / white wire at that " D " connector. If no voltage st the ohmmeter to ohms scale and check for continuity between that orange wire and the yellow / white wire. If you see OL that's not the same wire.

Or you could do it the easy way and trace it through the harness. I can't remember when I did mine. ( that was years and years ago ).
 
The new alt came in. It has a pulley that is smaller than the one I’m replacing. I think I like that. My crank pulley is a Vortec with built in accessory drive that’s underdrive. The smaller alt pulley will help out with charging at idle speed I suspect.

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