3g doesnt charge as well when hot??

[jmd2914]

when i first start my car the alt will put out enough voltage to keep the meter at about 13volts ( i think? its the stock meter in the car) but when it heats up it stays down around 10 or so. is this normal? or is something not working right?



Joel

 

[HISSIN50]

Take the car to the parts store for a free charging system test or take the alt in for a bench test (if the car might not restart).

Anything else is a guess because you really need a digital meter to do any diagnostics.

Good luck.

 

[Mustang5L5]

Heat increases resistance of wiring...so something in there isn't liking the heat. It could be a burning wire, or something internal to the alt, or simply a loose connection which resistance increases whenthe engine warms it.

 

[montegoman351]

What gauge cable are you using from the alt to solenoid?

 

[fastford91]

you should be using a 4G wire from alt to starter solenoid and a 4G wire for a ground!

 

[montegoman351]

At least!

 

[jmd2914]

i cant remember off the top of my head but its about the size of battery cable

 

[ninety15.0]

Mine does the same thing. When i first start the car it charges like 15 volts? (1 line above the middle) but once the car is fully warmed up it just sits at the middle line. And less than that when the lights and heat are on and the car is idling.

I am using 0 gauge from the alt to the solenoid. so i know thats not the problem and the alt tested out fine.

I do have underdrive pullies on the crank and water pump...but the stock pulley on the alternator. Does anyone have the name of that company that makes the overdrive alt pullies for the 3G's....is is ASP or something.

 

[jmd2914]

im also running u/d pullies on the crank and water pump, and stock on the alt. if they do make an overdrive alt pully i'd also be interested in where to buy one

 

[HISSIN50]

ASP makes an OD pulley. FFI also sells a nicely priced OD pulley.

Keep 3G alts under 15K RPM (you can calculate it if you know your crank and alt pulley ratios).

 

[montegoman351]

IIRC, the Aerostar 3G alt pulleys are smaller than normal...that'd make the alt spin faster. I'd go to the JY and measure pullies...but that's me...

 

[ninety15.0]

Thanks for the info hissin. I was just lookin at the ASP pulleys...but they are just so dam expensive for what they are...its ~ 25 bucks to get one of those to your door.

That being said i just bought one off ebay for 12.50 to my door. It's the same 1-7/8" 48mm overdrive pulley. Claims to add 10 amps at 800rpm idle. Thats the only time i really need it. Other than idle the thing charged perfect!