betelnut

If your alternator is going bad, 90% of the time it just needs new brushes. Don't trade in your original Toyota alternator for a refurbished one, and don't spend $120! Replacing the brushes yourself is easy as soldering, and costs only $3.

I did this on my truck last month, and finally got around to doing the write-up. You can see it here:

http://www.butchwax.com/2010/07/toyo...-on-the-cheap/

Hope someone benefits from this, and I welcome any suggestions for improvement.

Zelephant

Thanks a lot for posting this! I love cheap fixes that WORK!

JamesD

Here is an easier solution. For roughly $15, you can get the brushes and the holder all together at the dealer, no soldering. All you have to do is unbolt the old brushes and bolt in the new ones and that is it. I too did what you did and bought my brushes at NAPA. I then went to Toyota and they sold me the brush holder with the brushes. No soldering.

James

awdjunkies

Guess I am gonna have to try this out, thanks for posting !!!!

xxxtreme22r

I might "try" this with my OEM backup alternator, but not too sure it's a problem with the brushes, might be the Voltage Regulator.

betelnut

xxxtreme, take it to AutoZone or the equivalent. They can tell you whether the regulator is bad or not.

JamesD, learn how to solder! Making a good solder joint is a really satisfying feeling.

JamesD

Been a auto technician for over 15 years. I know how to solder. Why do it the hard way to save a few bucks? Unbolt and bolt back in. No soldering or chance for errors.

James

scope103

One of the problems with soldering is that solder never produces a strong mechanical joint by itself. I assume that the Toyota part is crimped together, which should be a longer-lasting repair.

With good technique and a little luck, the soldered joint should last a long time. But for a $12 savings ...?

thralldad

FYI a new regulator is about $25, so for a few bucks more while you have it out!!

xxxtreme22r

yeah I got to get that backup of mine fully cleaned and tested. been thinking about doing a gm alt swap with all this mud running I want to do. they are a little more sealed than the yota units.

swampfox

a toyota tech told me that you can check the diode pack with a volt /ohm meter. unhook all the wires from the alt. set the meter to ohms, place the pos lead on the large batt post on the alt ,neg lead to the housing.then switch the leads and check again. there should be continuity one way but not the other if the pack is good.

thinsley

Great thread and great write up. Thanks for taking hte time to share it with us!

betelnut

Touche! Still, if you know how to solder (and in my arrogance, I believe I solder better than the average factory worker), there's really no chance for errors, and saving $10 for 5 minutes of work (and in my case not having to drive all the way across town to the stealership) is worth it. And finally, I'm a big DIYer (a DIY-hard?) and I'll always pick the route where I do the work myself if possible. Of course I can understand there's a business case for a professional auto tech to save his time when he can just buy a new part and pass the cost along to the customer. But then, why not just buy a reman unit?

The original Toyota brush assembly wasn't crimped. As soon as I'd melted the solder, the brush popped out from only the force of the spring. The way it's designed, there should be almost no force on the connection; the brush doesn't move during normal operation, and the wire should be slack. It only has to withstand the force of vibration.

Hmm, interesting idea. I would've thought that the ohmmeter wouldn't supply enough voltage to overcome twice the 0.7v forward voltage drop of the diodes, but maybe it does (see http://www.autoshop101.com/trainmodu...or/alt126.html). Some meters have a special diode checking mode, maybe that's even better? AutoZone's test machine checks three different things, I wish I remembered what they were. I bet it would be easy to devise equivalent tests. From the diagram in that link, it looks like it would be easy enough to test all those diodes with the regulator out of the alt. At the same time, you could probably check that resistance of the coils is within an acceptable range, and check for shorts between the coils.

JamesD

Well yeah for you it is worth it but majority of the people on here may not have the skill or tools to do so. Most garages sell a whole unit. Your not going to pay the shop bills by removing $10 part and install a new one.

So how many miles are on your truck?

James

betelnut

Well I hope they learn! I love soldering, it's one of life's simple pleasures. Have I mentioned that I love soldering?

Agreed, the business case isn't there. I've heard most shops do a 2x mark-up on parts.

Almost 150k. If it turns out that the brushes went because of bad bearings, I don't mind pulling the alt once more.