Alternator diagnosis

[702_MJ]

My alternator has been giving me some trouble lately. It doesnt turn on every now and then i don't know if its a connnection or maybe the alternator is just going bad or maybe i screwed it up. But the guage will read about 12volts or less for the battery when i start it and it will either turn on and read 14 volts or a little over or it won't turn on and charge the system until I'm doin 65 on the freeway 15 min later. When i turn the blinkers on the needle fluctuates and moves. I don't know if its time to replace it or what? Oh and is there an aftermarket alternator thats like water proof or sealed and puts out more amps and all that good stuff? If there is or theres one you recoment let me know thanks.

[Eagle]

The "name" in heavy-duty aftermarket alternators is Mean Green.

 

I just went to Auto Zone and got one of their NEW (not remanufactured) house brand alternators. It has a lifetime warranty, so if I ever wear it out I'm covered. The one in the MJ is about 4 years old now and seems fine. The one in the XJ is about a year old.

[BLHTAZ]

Sounds like alternator time to me. I have used the "NEW" aftermarket starters from Discount and had good luck so far myself. I have not had the need for an alternator yet.

[pingpong]

Alternator is going bad. Get what ever one you want.. just make sure it is a NEW one. Also if you get it from advance be prepared to replace often. Remember not to overtighten the sepertine belt as it will cause premature failure, of the bearings in the alt

[FxRacing282]

it would be a good idea just as a precaution to get a voltmeter and check output from the alternator, should be around 14-15 volts

[702_MJ]

I want to get a volt meter and just make sure. I think when i recently went i got it a little soaked when i fell into a water hole, i had the water up above my 31's if that means anything. But its kinda a stupid design by jeep to have the alternator right level with the bumper. I've seen mean green in the quadratec catalog, but what about goin off road again, i want to go mudding again, i don't need to screw up another one.

[FxRacing282]

i woundnt worry about it ive seen tons of cars/trucks/minivans go 6 feet under and still make 14-15volts when running agian

[pingpong]

The design of where the alt is, makes it prone to the failure you describe. I suppose with a lot of work and research you can find a way to relocate it to the top. Personally I wouldn't buy one of them fancy expensive alternators cause of the design. Find a 140 stock alternator... that has a similar mounting patern.. and swap it out... also get the life time warranty

[702_MJ]

yeah but hey i can live with not relocating it, but what i was thinking is if its broke might as well upgrade. I plan to run lights on the truck and i thought the aftermarket alternator would help power them all, when i get them in the future you know. Because i want to run 4 lights on the bumper and 4 or 5 on a roll bar when i get one. Would a stock alternator even be able to put out that kinda power if they are all ran at once?