Picking correct alternator

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May 16, 2018 | 02:49 PM

#21

lionelhutz

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From: South Western Ontario

That looks like the connectors in the main power wires running from the under hood harnesses to the starter solenoid. One side goes into the under hood harnesses, the other sides runs to the solenoid, right?

If yes, then that is a fairly common connection to fail. A common way to fix it is to cut-out the connector and directly connect the wires instead.

I doubt those connections melting were caused by the alternator since they commonly fail on a car with a stock sized alternator.

Also, that isn't a connection I'd expect to handle 100A for very long or safely at all for that matter. That terminal type simply isn't suitable for 100A of current. I wouldn't even expect it to be suitable for 63A continually.

May 16, 2018 | 03:01 PM

#22

lionelhutz

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From: South Western Ontario

Quote:

Originally Posted by REELAV8R

At 75%, your voltage will be about 9.6 volts,

75% SOC should still be about 12.3-12.4V give or take. Also at 75% SOC, the internal resistance will not have changed much from the 100% SOC internal resistance either. It certainly won't be anywhere close to 1.3 ohms.

May 16, 2018 | 03:43 PM

#23

REELAV8R

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From: Hermosa

Quote:

Originally Posted by lionelhutz

Old battery lots of plate sulfation and grid corrosion. A brand new battery certainly not. Maybe 100 milliohms or less on a new battery, but then it's not going to be dead is it, or if you ran it dead with the headlights it's going to recover quickly, even without the alternator, which again, is not a battery charger.

Voltage is under load not free voltage. Even a 0% SOC battery is between 11 and 12 volts with no load.

May 16, 2018 | 04:08 PM

#24

lionelhutz

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From: South Western Ontario

So a bad battery then? A working battery won't be 1.3 ohms at 75% SOC, otherwise the car would never start even when that battery was at 100% SOC.

May 16, 2018 | 05:08 PM

#25

hardmansonfan

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thanks everyone especialy dubz & lionel i took those wires & connected them together directly with a crimp connector & duct tape the hell out of them.
as for the alternator i think imma go with around 80 range cause maybe in the future ill add more led lights in & around the car.

p.s. i forgot to mention my horns dont work at all so im going to eliminate them & adding truck or train horn. not sure if that's gonna determine alternator amps
p.p.s. good idea REELAV8R "parallel wiring" 🤔

Last edited by hardmansonfan; May 16, 2018 at 05:14 PM. Reason: spelling

May 16, 2018 | 05:17 PM

#26

DUB

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From: Charlotte NC

Getting your horns to work is often times an easy repair...or at least diagnosing the problem is easy. Or at least for me it seems to be easy.

I doubt your choice of horn will matter due to it isn't going to be on for that long.

DUB

May 16, 2018 | 11:10 PM

#27

The13Bats

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From: Eustis ( Area 51 Bat Cave ) Fl

http://www.onallcylinders.com/2015/03/27/alt-text-5-things-you-should-know-before-using-a-high-output-alternator/

https://alternatorparts.com/do-i-need-a-bigger-battery-wire.html

Disagree?

Be sure to call the company and tell them you think they are wrong im sure they will enjoy your feedback

Last edited by The13Bats; May 16, 2018 at 11:14 PM.

May 17, 2018 | 05:34 PM

#28

DUB

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From: Charlotte NC

I wonder what is the definition of a high output alternator is??? That can seem to be subjective. I guess it is an alternator that exceeds what the manufacturer uses when building the car is considered that.

So I am guessing that if a 105 amp alternator was used when building a Corvette...that would not be considered a high output alternator....or maybe it does.

DUB