Alternator power connection burned up again

[fbrdphreak]

UPDATE 5/14

So I took a further look a few days back and the alternator power lead definitely is definitely pretty corroded. See pic here. A buddy of mine had some high gauge cable and large ring terminal, so I've got a cable and connector ready to go.

The remaining challenge is splicing this into the existing wire. Obviously I will cut off just before where the wire is no longer corroded, but how should I go about splicing in something that large? I have solder and a small butane torch.

The only way I can think to do this, given it's a 1 gauge wire, is to fan the wires on each end out a little and literally stick them together, meshing together. I don't think twisting would work with wire this large. Then, smush them together, use the butane torch on one side of the wire to heat it, and solder on the other. Anyone have experience soldering wire this large?

Another thought could be to use a coupler like this: http://cgi.ebay.com/Stinger-1-0-Gauge-Power-Wire-Coupling-Splice-SPT8210-/400180598274

Any thoughts on the best way to approach this? I really want to make sure this connection will be solid.

Original Post:

A few weeks ago the battery on my fiancee's 2000 Nissan Altima drained unexpectedly. She got it home and I found that where the power cable attaches to the alternator, everything was discolored and fused from apparent overheating. When I tried to take the nut off, the alternator stud just broke off. I replaced the alternator, figuring it was just defective.

Now it's happened again. I don't know how fused it is, but I drove the car home and when I wanted to re-start it to move it in the garage, it wouldn't start. Battery was at ~11.7 volts and yep, the red cap over the alternator power connection was burned through even more. The nut/stud connection looks the same as before, though perhaps not as bad.

A little googling shows that either excessive current is being drawn via a short or that a problem in the connection or battery cable is causing high resistance and burning up the nut & bolt connection.

Here's a pic I shot of it: Link

The alternator is from Advance Auto and I believe is a remanufactured one, as is common. The alternator that was on there the first time was the same type. Her OEM alternator developed a bearing whine and I replaced it. The car has less than 2000 miles on it since the first replacement.

My plan is to see how bad the power connection is and hopefully the alternator stud is still usable. I will clean the shit out of those connections, make sure shiny/clean bare metal is there. Then I will inspect the alternator power wire and see if there's anywhere that could be problematic with it.

Some other sites suggest checking for shorts & check your fuses, but I have no electrical issues so I don't see why this is pertinent.

Lastly, I noticed while driving her car a couple times that when we parked it I could smell something like brakes burning. I couldn't note the smell down to anything specific and the brakes appeared fine. I'm guessing this burning the insulating cap was that smell.

Is there anything else I should check? Any other suggestions?

 

[cprince]

Some other sites suggest checking for shorts & check your fuses, but I have no electrical issues so I don't see why this is pertinent.

Lastly, I noticed while driving her car a couple times that when we parked it I could smell something like brakes burning.

So....you don't think these two are related somehow?

I'm 99.999999% certain that you have a major short somewhere near the alternator output.

 

[fbrdphreak]

So....you don't think these two are related somehow?

I'm 99.999999% certain that you have a major short somewhere near the alternator output.

Sorry, my point was that I think that burning smell was the cover on the alternator power lead. You can see it a bit in the pic - it's roasted.

 

[Meghan54]

Sorry, my point was that I think that burning smell was the cover on the alternator power lead.

That may be true, but sounds like you've got a horrible short somewhere near the alternator. I'd start the unenviable task of tracing the wiring coming off the alternator for a start....and maybe backward trace the + wire from the starter and battery. Bet you have some chafing on one of your major + cables and don't easily see it.

 

[alexruiz]

How clean is the cable that attaches to the alternator? The connection there must be tight and CLEAN at the contact surfaces. I am suspecting poor connection, hence high resistance, which leads to higher power dissipation at the connection, and the power dissipation is observed as HEAT.


Alex

 

[SpatiallyAware]

I would be suspicious of the alternator, primarily since it's from advance.


My ranger is extremely picky about the DPFE sensor outputs.. I went through 2 advance auto sensors before I pulled my meter on it and discovered that they were WAY off. Went and grabbed one from napa that read perfect.

 

[LTC8K6]

I would be suspicious of the alternator, primarily since it's from advance.


My ranger is extremely picky about the DPFE sensor outputs.. I went through 2 advance auto sensors before I pulled my meter on it and discovered that they were WAY off. Went and grabbed one from napa that read perfect.

Sometimes it's hard to believe that the engine computer is right!

 

[fbrdphreak]

bump for update

 

[fbrdphreak]

bump for feedback?

 

[NutBucket]

I would try to replace the whole cable. USUALLY it will terminate in the under-hood fuse box and possibly the battery. If the end of the cable is that bad, chances are that there may be some other damage that is hidden by the split loom.

 

[fbrdphreak]

I would agree, but the cable is worked into a wire loom that circles the engine bay and disappears into the fender well. I'm also betting that the damage is just corrosion where it is exposed at the end of the wire. This car is 12 years old and the part that is corroded was not directly covered with insulation, just the red boot.

 

[PottedMeat]

you could do the meshing then soldering thing, but make sure you slide some heat shrink on afterwards.

the coupler would work, but i think i'd crimp a piece of copper pipe on the splice, solder, then cover with heatshrink - but i have junk like that laying about heh.

 

[LTC8K6]

http://www.delcity.net/store/Copper-Compression-Splices/p_1010.a_1

 

[fbrdphreak]

That's an interesting option. Do you just crimp those then?

 

[WackyDan]

That's an interesting option. Do you just crimp those then?

Tim,

I would in combination. I've done the same with some pretty stout motorcycle battery cables. Crimping, then Soldering will ensure a solid connection and eliminate potential for corrosion.

Next, as someone already suggested... Heat shrink it, but not just with regular heat shrink... use Sumitube W3B2. It is heat shrink with a resin/glue inside that will seal out any moisture that may get near that splice.

Northern Tool carries something similar, but I don't know if their shrink is that large. It is otherwise kinda hard to find, and I've always gotten mine from Japan. I've never had an electrical connection failure on any of my splices on the bike.

 

[5150MyU]

NAPA has heat shrink w/glue.
Go to their web site and search "heat shrink tubing", they have double wall and heavy duty.

 

[Eli]

I would do as you say, fan the wires so they mesh together, then crimp them together(to reduce the diameter of the crimp), solder well, and apply heavy duty heatshrink.

It's going to be difficult to solder wire that large. You might need a fairly beefy torch. Don't forget flux. It will make things go more smoothly.

 

[Howard]

Western union splice, then solder ONLY THE CENTER (leave the outer edges of the splice non-soldered). In the center, do make sure you get full penetration, though.

 

[fbrdphreak]

http://www.delcity.net/store/Copper-Compression-Splices/p_1010.a_1

Tim,

I would in combination. I've done the same with some pretty stout motorcycle battery cables. Crimping, then Soldering will ensure a solid connection and eliminate potential for corrosion.

Next, as someone already suggested... Heat shrink it, but not just with regular heat shrink... use Sumitube W3B2. It is heat shrink with a resin/glue inside that will seal out any moisture that may get near that splice.

Northern Tool carries something similar, but I don't know if their shrink is that large. It is otherwise kinda hard to find, and I've always gotten mine from Japan. I've never had an electrical connection failure on any of my splices on the bike.

Is this the same idea as what LTC linked? If those tubes are the same thing as these, but just a connecting tube instead of a lug tube, I think I'm in business.

http://www.youtube.com/watch?v=SXDkNMDDrBs&feature=related

 

[5150MyU]

http://www.youtube.com/watch?v=SXDkNMDDrBs&feature=related
Remember it says closed end connnections---you got some modifications to do if you want it to work on your basic connecter.

 

[WackyDan]

Is this the same idea as what LTC linked? If those tubes are the same thing as these, but just a connecting tube instead of a lug tube, I think I'm in business.

http://www.youtube.com/watch?v=SXDkNMDDrBs&feature=related

I'm betting that is different... I would order a few just to check it out. Bets are that that tube is open all the way through, and just as the indent or a rim as a stop internally. If it has a solid divider, then those are actually pretty freaking nice.