Frustrating alternator/electrical issues

[brady1971]

Newer here and never posted before, so bear with me.....

I have a alternator power issue with my bronco....I have installed several 1 wire alternators....2 from Jeg's and 1 from Tuff Stuff. Single pulley 140 amp units. I am using 6 gauge wire from the alt to the battery. New Optima red top battery. Toms LED headlights and advance Auto LEDs for the running lights. I replaced the wiring harness about 4 years ago using a Centech.

I understand a 1 wire and needing to blip the throttle to excite the alternator...On my truck it has always charged at idle. Just over 14 VDC. Now, as soon as I turn on my fan or headlights the voltage drops to 12.5 with a little gas it will start to rise but only very slowly. Its like the voltage regulator is in slow gear. At an idle with no blower fan or headlights its starts low and very slowly comes up to the 14.5 VDC but slowly....over 5 minutes.

No belt squeal at any RPM...All 3 alternators test good on the test stand....alternator pulley diameter is 2.25" and crank pulley is 5.75". Added extra grounding to the engine, frame and chassis.

Kinda stumped here....any thoughts or advice?

 

[.94 OR]

I am no electrical wizard, but I am about to install a "1 wire" alternator into a Toyota 22R. I did find this thread that has more information than I needed so scan it over.

https://www.pirate4x4.com/threads/1...lavista-pirate4x4x-com.2702737/#post-44988321

 

[Rightpace]

Take out the optima battery and install a regular battery.
I believe you will find that the alternator will work normally.

 

[brady1971]

Thanks for the comment.....I installed the Optima just yesterday out of guessing more than anything. It has had a Diehard in there for all of this testing.

Can a short pull this much power? No fuses blown....not hot wires that I can feel.

I am going to start unplugging lights one at a time to see if this can lead anywhere.

 

[brady1971]

Thanks 94OR.....i need to get a cup of coffee to read this article.....alot of info.

Lived in Salem for years....miss it. No one knows what Marion berries are east !!!

 

[AZ73]

I just wired up my "1 wire" alternator" and after reading a bunch on how to do it, the basic conclusion is it was the lazy man's way to wire it up and it will cause problems, especially if you don't have a resistor (or idiot light) to help excite it. I ended up using the 3 wires AND a ground, making sure to put the 1 wire AFTER the fuse to let the alternator know if it was producing too much (enough to blow the fuse) and shut itself down. This was one of the information sources I used:

https://www.ford-trucks.com/forums/1458070-help-with-3g-alternator-wiring.html

 

[brady1971]

Found a short on the front running lights drawing it down. Cleaned the socket and changed the bulb. Looks to be good now. Still a slower than I would like ramp up to full power. Thanks for the article very informative.

 

[gr8scott]

I've had no problems with my 3G/Yellow top combo. What really helped was grounding the back of my alternator case to the battery negative
ground point on the engine block. Gives the alternator a direct path to battery negative as opposed to going through ten head bolts and two water
pump bolts.

Are you using relays for the lights and fan? Also, 6 gauge should be adequate, but you may consider stepping up to 4 gauge.

 

[brady1971]

I have it grounded to the alt itself. I read on past post about bronco's with ground issue. i have it grounded to the block from the battery...with another from the block to the frame. A few from the frame to the body in the back and 2 up front from the frame to the body. Mech fan....I do have the LED wiring harness from Tom's to match the LED headlights. Charging now...just the slow build to full power worries me a bit. Takes about 2 minutes....it reaches 14.6 VDC. Just expected it to be more instantaneous.

 

[DirtDonk]

I don't know the characteristics of one, but could this be the result of a "soft start" type voltage regulator? They're designed to keep belt squeal away, which is particularly handy with V-belts on the Ford alternators.

Is your 1-wire a Ford or GM alternator?

Paul

 

[brady1971]

It is listed as a hybrid...Ford front with GM internals...I believe they use the 10si or the 10CS (?).....Tuff Stuff brand. Driving it around for the yesterday it seems to be fine to charge. Maybe it does pull in slow to avoid belt squeal....I will give it a good test...plan on driving it down to Townsend...it will be the first time...excited and a little lost for the process.