User 051420

After kicking ass in a game of Pictionary, we all thought it would be fun to take the 4Runner out at 1am to do a little mudding. Right on, we had a lot of fun and got way dirty. Didn't get stuck, and nobody got hurt. Yay for us, right?

Well, on the way home my battery light, ABS light, and brake lights come on. It was like a Christmas tree. I immediately knew it was my Alternator. So I drive it home, and slept. Earlier today I go out and take it to the car wash to rinse everything off and remove the little mud from the alternator. Woo hoo, the light goes out. THEN all hell breaks loose. I'm driving the hour trip to Sacramento and the light comes on again. While going about 80mph in the fast lane, all power is lost, my lights dim, everything. Somehow, I make it over to the shoulder and stop. CRAP..the truck's pretty dead. I wait 2 hours for a tow truck to drive me home, the alt tests bad so I blow $266 on a new alternator, and install my new alt at 10:30pm. (I can do it in 25 minutes now, btw). Yay, the truck works and it seems to be charging properly.

Now on to my question....the alt I pulled was my 150amp Mr. Alternator..MUCH better than the 70amp I got from NAPA. What can I do to repair the old alt? Is it worth fixing? Anybody have an idea? Anybody want to buy a near new 70amp rebuilt Nippon Denso Alternator?

jimbo74

give mr alternator a call, and see if they will warranty it, dont tell them you wnet mudding though... and next time, put some inner mud guards or something to help cut down on exposure if its possible

Flamedx4

Depends on what went wrong, but alternators are easy to repair. Harder may be getting parts for a "Mr Alternator" unit... I bet all that went wrong was a diode or three blew. Tear it apart and see! (First see if they will warranty it. Pity you didn't do that before buying a new one...)

User 051420

Just a little update..I took the alternator to a local shop, and they fixed it in an hour. It turns out that the brushes were entirely worn out, with no contact left. Thats pretty crazy for ~5k miles.

Anyways, $28 later my old alt works again! Now to return the new one..

Fink

Good to hear man, mudding is a heck of a lot of fun, especially with a bunch of your good friends but it can be hell on your rig.

Not to hijack or anything but I have been looking for a high-output alternator and I'm wondering if the 150amp Mr. Alternator you have would work with my 2nd gen...are they pretty universal or would I need one made for my rig?

Hope everything else cleans off and runs well for ya!

Fink

superjoe83

thats really strange for a set of brushes to do that, they don't really have much load going through them, probably just defective

HondaTec521

Or the MUD ground down the brushes............................

BruceTS

I doubt the mud wore the brushes out that fast, I go muddin all the time and my stock alt hasn't had any problems. It could be the carbon material Mr. Alt. brushes use is too soft or the higher output put too much of a load on them.

Flamedx4

Years ago when everyone started winding for "high output", brushes and brushholders actually burnt on some units! Stage 2 was heavier brushholders and then bearings died... In RVs where the alternator has to work really hard the big alternators that survive are physically big, big bearings, big brushes, lotsa air circulation, and big dollars! If you use a winch or even just have a lot of aux lights you might find that a stock alternator lasts longer than aftermarket "high output" units, unless you pony the real money and get a good one. (I'm not saying this "mr alternator" unit isn't any good, I've never heard of them.)

3car

good luck on that one.

Flamedx4

Great avatar 3car! Time for a new pic?

3car

yeah, it probably is. I've been lazy lately