Lightning Rodder banner

Alternator out

5K views 30 replies 13 participants last post by  hector svt 02 
#1 ·
Well a couple of months ago I got my truck back from being built and about 3 weeks ago my batter light came on in the truck I thought it would be my battery but got it swapped out and still had the same problem with low voltage , at idle it would go as low as 11-12 volts once even saw 10v on my aeroforce..I have a electric fan for the radiator and two for my heat exchanger and 255 pumps, interior I have 3 gauges and a touch screen that's about it, I've tried reading on the old forums on what kind of alternator I should go with but almost all of the posts were pretty old so I was seeing if there were any new suggestions out there and if a 200 amp would be best? But from whom and reputable manufacturer?

Thanks in advance
 
#2 ·
Mine went out in 2014, same as yours. Thought it was the battery, but nope, alternator. I didn't have any huge load draws at the time, so went with a stock 130 amp from NAPA. I do have two HE fans in my garage now, but they will be wired into a toggle switch, for use at nap-inducing stop lights only. So I'll see if I need to get a higher output alternator.
 
#3 ·
Yes from what I've been able to see the heatexchanger fans draw a pretty good amount... I've heard good things about the NAPA alternators as well...do they make 200 amp series?
 
#5 ·
My experience with these alternators...
The diodes get HOT from the current draw, they open and no longer have output. When the diodes cool down they close and work again.
So taking it off the truck and having it tested, it will show good.
How hot is your alternator getting?
My alternator consists of
70amp bridge rectifier
200 amp stator
Stock 130 rotor
HD voltage regulator
1.9" pulley
 
#9 ·
My experience with these alternators...
The diodes get HOT from the current draw, they open and no longer have output. When the diodes cool down they close and work again.
So taking it off the truck and having it tested, it will show good.
How hot is your alternator getting?
My alternator consists of
70amp bridge rectifier
200 amp stator
Stock 130 rotor
HD voltage regulator
1.9" pulley
Also did you get yours custom made at a alternator shop?
 
#6 ·
It's nice to know that NAPA has the 200 amp as an option. I may consider one after I get the HE fans on. We'll see if it's necessary. As I said, they will be wired to a switch, and only be on at nap inducing stop lights. There's no need for them to be running once vehicle speed is north of, say 25 mph. If what Certified Drunk says is true, may not even be an option at all.
 
#8 ·
Certified drunk I'm not shure on that I just took it to my auto parts store and got it tested and it failed so I couldn't tell you exactly...and about the upgrade wiring kit for the alternator, I installed the upgraded battery wiring kit from harley#356 I should be good with that right?
 
#11 ·
200 amp alternator seems to be the sweet spot for these trucks. I didn’t have issues last year, but I’m adding a remote bridge rectifier this year to help with the situation CD was describing. Should bring temps down and improve reliability. May even see less of a voltage drop during the summer months getting that heat out of the alternator.
537798
 
#13 ·
the big ol cooling fan on the side may allow for a little water intrusion.. I'm guessing this would be mounted in cab?
 
#14 ·
That looks good, also curious about where it would be mounted
 
#16 ·
Yeah my truck doesn’t get driven in the rain. Either way, it’s no different than the back of your exposed alternator which holds the factory bridge rectifier. mine is getting mounted next to the battery on the firewall. I may make a little shield for the vent ports with a 3D printer I have at work, but only because it’s right under the rain tray. Either way I’m not concerned. It’s way more enclosed then the alternator is.
537804
 
#18 ·
Soooooo my alternator went out again yesterday night...so that puts me at about 7 months when my first one went to crap ...battery was not holding charge....I have a napa 130amp and im probably going to have the warranty replace it....anything else it might be or might want to check out when having the alternator out? Also, i have Harley# 356 super stock wiring put on it when my first alternator went to sh!*
 
#20 ·
Does anybody know the napa 200amp alternator part number i tried looking for it online but can't find it
 
#22 ·
Do I need that connector even if I have the upgrade wiring from harley#356?
 
#23 ·
I don't believe so.. I sure Josh used larger gauge wire to handle the higher amperage output seeing that he also runs a high output alternator.
I've not seen any of his wiring kits but, if you replaced the stock small gauge wire with his kit, it would be a larger gauge and that he made them to handle 200 amps...
 
#25 ·
So after finally getting into installing the alternator, comes out that the alternator is not a direct fit.so I will be returning it and thinking about just getting this one instead

.https://www.americantrucks.com/paperformance-200-alternator-9904-lightning.html
 
#26 ·
Has Anybody ran this 200 amp pa performance alternator before?
 
#30 ·
I'm currently running one and it's awesome. The alternator paired with Josh's Big 3 upgrade is the way to go! I run a Fore hat with 3 pumps, sound system minus the subs, hid lights, multiple guages, radar, dual widebands and the voltage is constant and stable. Highly recommended it.
 
#29 ·
Tried a 240amp J2 Fab and it was junk until it was fixed correctly.
 
#31 ·
Awesome thanks guys I appreciate the input.I just got one ordered hopefully it all works out...if all fails I'm thinking about just rebuilding one the way certified drunk did
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top