Is it feasible to "rebuild" an alternator that is making a whining noise, presumably due to bad bearings? If so, where does one find these "rebuild kits"? And finally, is this a job that can be done easily or does it require expensive equipment, such as a hydraulic press for some parts of the rebuild process?
There doesn't seem to be much info on the net about doing it yourself and even less about where to obtain these mythical kits.
That would depend on a few factors, including how the case is closed - those that are pressed, riveted, or worse, welded together, are going to be much more difficult, if not outright impossible, to get inside and work on than those that are bolted or screwed together.
That's because these days, even by the standards of professionals, an alternator is almost universally considered a "replace as a unit" item, rather than something to attempt to make repairs on. And in at least some cases, they've got good economic reason for thinking so - What's cheaper? Go to parts place and buy an $80.00 reman, or pay your $65/hour mechanic to sit there at the bench for 2-3 hours playing with repairing an alternator? You got it... The shop is going to go buy the new/reman rather than attempt to diagnose/repair the old one.
Many "non-professional" people think of them as a rather mysterious, maybe even "magical", black box that dare not be opened for any number of reasons (some good, some bad, some incredibly stupid). Over the years, I've also noticed that "Joe Shadetree" tends to have a pretty serious aversion to messing with anything that involves electricity - even the nearly risk-free 12 volts present in a car. Don't ask me why, but that seems to be the case. (before the nit-pickers attack and try to tell me that 12 volts isn't risk-free, please note my very careful and deliberate usage of the word "nearly" in conjunction with the phrase... I'm quite aware that it is indeed *POSSIBLE* to do yourself harm with it, but it's not at all EASY to do so without weird conditions that usually aren't encountered.)
As for me, I'm driving a car whose factory manual includes a section on testing/disassembling/repairing the alternator at the component level, and I also have a spare, known-to-be-good, alternator sitting on the shelf for it from the wreck. So my future plans are pretty well set: if/when the alternator on the car currently pukes, I'll simply swap in the one sitting on the shelf, and as something of an "adventure", pop the "dead" one open and at least *TRY* to repair it. If nothing else, I'll have earned the "bragging rights" such a deed might be worth.
If I can slap in a 30 cent diode using a nickel worth of solder and a buck worth of electricity, and end up with a works-like-new alternator to put back on the shelf for next time, doesn't that make a lot more sense than going out and dumping the $65+ price of a "rebuilt"/"reman" unit, PLUS handing my old one (Alternators are "core" parts anywhere I've ever been - no old one to turn in equals some ridiculous charge added to the price of the new unit) to somebody else *ESSENTIALLY FREE* so that they can do exactly what I'm planning on doing before they sell it back to me for 65 bucks and tax? I think so. I don't expect to "get rich" or anything like that with the savings, but hey... A couple bucks worth of materials and an hour or two of diagnostic/repair time spent on something I find enjoyable to begin with (electricity and/or electronics is FUN, as far as I'm concerned) sure beats the hell out of paying $65+ bucks for an alternator that's been repaired in exactly the same way.
Well I did this for the alternator on my '73. I heard a loud whining noise, and the alternator had made noise like that in the past but at very low volume so I jumped to it as being the problem and replaced the bearings in it. I got them at napa by asking for the bearings specifically. (The loud whining noise turned out to be something else, but the minor noise of the alternator went away for good)
Basically if the alternator is in good shape otherwise replacing the bearings is probably a better option than alot of the remans out there.
Our local parts stores, Canadian Tire sell the rebuild kits. They come with brushes and springs for them, the bearing, the big diode and the regulator.
You need a pulley remover and a bearing puller which our local parts store will 'lend' out for a safety deposit you get back.
They are not difficult to rebuild, but you have to be careful, some have parts soldered in place that need unsoldering to completely pull them apart. The brushes also need to be soldered (the wires) on most of them.
I recommend a couple days of soaking the long bolts that hold the case halves together with a good penetrating oil before going after it. That seems to be the most common 'oops' that I see.
WD40 makes an excellent cleaner for the insides, it gets all the crap out and doesn't conduct. It is not good for a penetrating oil in this situation.
Same deal goes for starters. They are really easy to clean out and refresh with new brushes and end bushing.
I off road lots and mud is a fast killer for starters and alternators. My friends and I just open our starters and WD40 the crap out of them to loosen up seized brushes and mud packed gears and regrease and seal then with dielectric grease at the seams then away we go for another season. We usually don't even need parts, just a good clean.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT'smZ wrote:
Been years ago, but I put bearings in one from a 1980 Pontiac. It was whining. Went to parts store and asked for bearings. No big deal. I think they had brushes also, but I didn't change. Used basic tools (wrench, screw driver) and a hammer and punch to remove bearings. Not sure how all alternators are put together, but did this one in the parking lot of an appartment complex...
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