when is a stock alternator not enough?

2wd-fire · Dec 19, 2012

Extended Power said:
I just replaced my stock alternator with a 200amp unit from Mean Green.

Even though the old alternator was still working, (With an overdrive pulley on it) I have Flex-a-lite fans which pull 30-40 amps all the time...and the stock alternator is in no way ment to be on our trucks...they are a POS.

New alternator on...I got 14.2vdc right after the truck starts, and is at idle. NEVER going back to stock alternator again...even if someone paid me to take one...

This!!:ford:

Lassie · Dec 19, 2012

Someone is selling a Singer 220 amp alt on the Engine and Drivetrain Forum now.

chappy · Dec 20, 2012

Extended Power said:
I just replaced my stock alternator with a 200amp unit from Mean Green.

Even though the old alternator was still working, (With an overdrive pulley on it) I have Flex-a-lite fans which pull 30-40 amps all the time...and the stock alternator is in no way ment to be on our trucks...they are a POS.

New alternator on...I got 14.2vdc right after the truck starts, and is at idle. NEVER going back to stock alternator again...even if someone paid me to take one...

Damn I'm jealous!

Someone is selling a Singer 220 amp alt on the Engine and Drivetrain Forum now.

Used? I really hate to buy something electrical like that used.

Jarrod B · Dec 20, 2012

mine hovers between 11-14. but i really dont have much aftermarket accessories. but i hate my autozone batts tho.

Lassie · Dec 21, 2012

chappy said:
Damn I'm jealous!

Used? I really hate to buy something electrical like that used.

No, brand new. He had two on a rack he wanted to clear out. One sold already, has one left.

chappy · Dec 21, 2012

Jarrod B said:
mine hovers between 11-14. but i really dont have much aftermarket accessories. but i hate my autozone batts tho.

Really? Autozone batteries are made by johnson controls and they are suppose to be one of the better battery manufactorers. They make sears die hard,duralast,optima,and even motorcraft batteries. I have always had good luck with motorcrafts. I just changed my wifes 05 f150's original battery last month. 7 years old and was still working fine but with the cold it was starting a little slower.

chappy · Dec 21, 2012

Lassie said:
No, brand new. He had two on a rack he wanted to clear out. One sold already, has one left.

Alright thanks bud. I checked it out and its a little steep for me especially this time of year.

chappy · Dec 22, 2012

yeah The alternator failoed autozones little tester so they gave me a new one. I now get 12.5 volts at idle with everything on. It goes up to 14v going down the highway. I made a cool little tool for moving the belt tensioner over to get the belt off. The ones from autozone and such are at the wrong angle and its a pain to get a rachet down in there so I made a serpentine belt tool. My kickstand doesn't work either so that made it fun as well but not now. I think I'm gonna try an overdirve pulley for now since whenever the alternator craps out I get a new one for free so if it eats up 1 a year so be it. Heres the source for the pulleys. Half the price of what doug was selling them for. My fuel pressure still drops at idle if I have lights on and heater so Its still not enough. My guess is the little fass helper pump pulls a lot of amperage.
http://www.cpgenerator.com/overdrivepulleys.html

chappy · Dec 22, 2012

Well I bought this one since its cheaper and in Michigan. We will see what happens.
http://www.ebay.com/itm/OVERDRIVE-8...Parts_Accessories&hash=item27cb07d0f6&vxp=mtr

Extended Power · Dec 22, 2012

I don't think over spinning the alternator helps at all...maybe in stop and go traffic, but when I drive my truck, the engine see over 4000 rpm at times, and with the smaller pulley, the alternator is spinning close to or over 12000 rpm...

F-250-Owner · Dec 22, 2012

Not to derail..but I just put a 200 amp unit on mine it charges great..... but if I smash the skinny pedal...all of my accessories cut out... I am thinking I may need to add another positive wire from the alt to the battery

Sent from my SPH-L710 using Tapatalk 2

guillozet08 · Dec 22, 2012

Dont.buy autozone pos. Problem solved

scparrish · Dec 22, 2012

I went through 3 autozone batteries in a month and a half, granted I have a lot of aftermarket electrical going on, but I got a dc 260a alt and couldn't be happier.

chappy · Dec 22, 2012

Extended Power said:
I don't think over spinning the alternator helps at all...maybe in stop and go traffic, but when I drive my truck, the engine see over 4000 rpm at times, and with the smaller pulley, the alternator is spinning close to or over 12000 rpm...

Yeh I've been looking so far and what I can come up with is as long as you are under 18,000 rpms on the alternator your safe so I should be good. I know its a bandaid but I just don't have the cash to do it right. The ones Doug from gogo diesel was selling a couple years ago were even smaller then this one and he wasn't having any problems.

Jarrod B · Dec 23, 2012

chappy said:
Really? Autozone batteries are made by johnson controls and they are suppose to be one of the better battery manufactorers. They make sears die hard,duralast,optima,and even motorcraft batteries. I have always had good luck with motorcrafts. I just changed my wifes 05 f150's original battery last month. 7 years old and was still working fine but with the cold it was starting a little slower.

Well I have the red top ones. They came with the truck. If I get autozones again ill get the gold top or the gel ones.

bluedge8 · Dec 23, 2012

Extended Power said:
I don't think over spinning the alternator helps at all...maybe in stop and go traffic, but when I drive my truck, the engine see over 4000 rpm at times, and with the smaller pulley, the alternator is spinning close to or over 12000 rpm...

over drive pulley will help to raise voltage at idle, as most alt's are designed to put out max amps @ higher than idle rpm, so since he is having an problem at idle only, the pulley should help

chappy · Dec 23, 2012

bluedge8 said:
over drive pulley will help to raise voltage at idle, as most alt's are designed to put out max amps @ higher than idle rpm, so since he is having an problem at idle only, the pulley should help

That is where I'm having problems so thats what I'm hoping.

Qholic · Dec 25, 2012

I just put an AdvanceAuto 140 amp made by Worldwide. It comes in the larger 6g housing and puts out 14.0-14.2 at idle with everything powered up. It was 155 bucks but there was a 20% discount if you ordered through their web site--picked up at the local store. Hopefully it will last until I can save up for a 200+ amp version.

Zmann · Dec 25, 2012

F-250-Owner said:
Not to derail..but I just put a 200 amp unit on mine it charges great..... but if I smash the skinny pedal...all of my accessories cut out... I am thinking I may need to add another positive wire from the alt to the battery

Sent from my SPH-L710 using Tapatalk 2

I'm thinking you have another issue I would recheck all battery connections

GatorBaitR6 · Dec 25, 2012

Yea I went by advance for a batt test they told me the batts were good at 12.5 and 12.4 truck off... when I saw 9.5-10 on start the other morning and 12.3 at idle 13.5 drivin down the highway...