Autozone alternator

[TimpanogosSlim]

in regards to #2, an alternator doesn't force current through a wire. The amperage is determined by the draw of each individual item in a circuit so the myth that existing wiring can't handle the load is just that, a myth mostly promoted by vendors that only offer stock replacements

This is true. And the thing is, replacing that wire will often improve the connection strictly because the old wire had corroded ends.

My land cruiser has a 95A denso and it's said that in normal operation with the AC on and the stock radio going, headlights on, hurtling down the road, the draw is about 80 amps. The lead from the alternator appears to be maybe 6ga if i am being generous.

Sounds puny compared to the massive upgrade cables you can buy, right? But if you refer to the engineering table, 6 AWG wire is rated for 101 amps chassis wiring. It's less than half an ohm per 1000 feet, and that lead to the battery is less than 4 feet long. It's fine.

When i install a 150A alternator out of a sequoia in the LC to support a 2nd battery for camping, I'll upgrade it. Probably to 4ga. For the safety margin, because a deep cycle battery charging from deep discharge is going to put a lot of load on it.

[daved]

in regards to #2, an alternator doesn't force current through a wire. The amperage is determined by the draw of each individual item in a circuit so the myth that existing wiring can't handle the load is just that, a myth mostly promoted by vendors that only offer stock replacements

Exactly right Mark, only way the high amp alternator would overload the wiring is if you had accessories that required more current than the wiring was designed for.

Back to my original question. Did try to buy an AutoZone alternator from their website. Seemed to indicate it was in stock & let me put it in the cart. When I actually tried to check out it said it wasn't available. Instead bought a new alternator for a 1977 & up Spider. Required some wiring changes & a slightly longer v-belt but seems to be working well.

[spider2081]

When i install a 150A alternator out of a sequoia in the LC to support a 2nd battery for camping, I'll upgrade it. Probably to 4ga. For the safety margin, because a deep cycle battery charging from deep discharge is going to put a lot of load on it.

I think this is the point the writer of the link was making. If the cars battery is discharged like to the point where it needs a jump to start the car, the higher output current alternator could put out more current than is safe for the existing wire. The original alternator has a limit as to how much current it can direct to the battery then the alternator goes into saturation and it just can not produce any more current. The original wire should be safe for that amount of current. i know the more the battery is discharged the greater its internal resistance is and this limits the charging current, I just don't know what the maximum current is that a discharged battery could draw. I think its pretty high.

The other draws on the alternator like lights and fans operation remain the same as is stated their demand on the alternator is what it is regardless of the alternators amperage rating. I think a discharged battery though can draw more current from a higher out put alternator than the original alternator.

[DieselSpider]

And if your installing bigger because the stock alternator can't keep up with the load then its more likely that the overload situation already exists. You really need to get to the root cause of the problem before installing a bigger alternator. The weak connection/overloaded circuit/partial short is still going to be there overdrawing afterwards with the potential for more dramatic results.

If your not putting in an insane off road light bar, extreme high draw electric heaters, mega gigawatt sound systems there is really no need for a super sized alternator from a 150+ hp vehicle in the simple Spider. Its a little car with a low powered motor by today's standards that can be quite a fuel efficient reliable car if you keep it simple and don't go overboard.

[pjnats]

"Diagnosis by replacement" can be expensive and frustrating. Look for a local business with knowledgeable people and the ability to rebuild on-site. Maybe somebody like this: http://eriebataltstrtr.com/

I'm having an issue with battery or alternator and during my search I came across this post. What really surprised me is that you provided a website for a company that is in my hometown, Erie, PA! I see that you're in Baltimore; how did you come up with this site?