How To Repair an Alternator – Voltage Regulator

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If your bearings, housing, or spindle are not messed up then just replace the regulator and points! This has worked for me at least 6 or 7 times. I hope this works as well for you guys as it has for me!


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37 Replies to “How To Repair an Alternator – Voltage Regulator”

  1. Thank you for this information. Even though my car is not a Porsche, I was able to implement your advice towards my car and you are on target.
    Changed my regulator which showed uneven wear to the brushes and now the alternator is running perfect.

    Thank you.

  2. orangestoneface
    1 second ago
    for nissan almera .15 liter 2003 or. not charging..since this vid is a feasable coice of results for search for my prob, l will describe double coal one too short repair. push in tab on connector f wires to release, four bolts f casing , first release all small bolts on top , open, l used hammer on casing boltholes alternatively, to pry open . its a rather hard repair , difficult fittings not designed for public , nuts off yellow bigger bolts two on regulator and beat them down w hammer. later needs rather much force in same way on assembly. take a pic on each step to know assembly maybe. needs much twisting to get out , under is cols brushes in plastic, will not come out, so l bent one bolt hole metal down to get it out , the one that reaches under diode halfring. in shop dont ask for just brushes if you send a buyer , ask for brushes in plastic fastening. so l did not want to try to put in bare brushes l had so l pulled on the short brush with pliers to make it come out stretching the spring and it came out one or three millimeters , will last some months l guess. thats about it for now, ask me if in trouble. bearings felt loose, opened one to put grease, might wanna drip thick gear oil on other in a tight spot or some fluid grease but might make trouble with wiring spools.

  3. I agree with Philip and Mojo. Lack of knowledge and too much talking…Useless video if you want to learn how to repair voltage regulator (not how to exchange).

  4. I have a Passat vw 1999 I took it to get it tested the everything out the starter was good the battery is good but the alternator failed because of the regulator. so my question is it better for me just to replace that or the whole alternator? (we had just installed a brand new alternator in November/December)

  5. you need to turn a few wrenches,learn the actual name of the parts your fukin wit and grow some fuzz on your nuts…before you can play "master automotive tech" if you Internet "instructional douches" are learning while your taking shit apart….or mimicking other doucshes videos….your just gonna "help" people mess up their vehicles…or vei!!

  6. Great video. General Q:
    When the alternator is out, how can you tell its the brushes (or carbon tips?)
    The alternator is removed, as is the voltage regulator. The two brushes make good contact with the spinning arm; but will the arm/spindle show a sign as to whether there is sufficient contact? Such as: If the arm/spindle is blackened does that mean they're bad since there is poor and relatively light scratching. And conversely, if the arm/spindle is smooth and copper colored (at of course the contact "road"), does that mean its a good contact? Or should I not make those conclusions? In any event, my arm/spindle is blackened.
    Thank you again!

  7. I have two 944 and was sharing one battery (since one 944 is a project which was running until recently ):
    WHITE 944 is Storm lol
    NAVY 944 is Beastih (my current project).
    I was moving the battery from one car to the other. i wasnt tightening the battery cables :/. First sympton from Beastih, belt was squeaking. then a week later she kept powering off at every STOP, she would fire back up. until last week she didnt fire up at all.

    Storm had a squeaky belt for about a month earlier than Beastih. She still runs but when i turn me heater on, the battery gage drops to 10 and my belts sqeaks. now squeaks more often. I had my alternator tested and the Voltage regulator failed test. So i ordered one.
    now my question, How can i figure out what i need to replace for Beastih? Since both have different symptoms. Beastih doesnt fire up at all.
    Do you think i need a new alternator? MIGHT just need to replace the bearing, brushings, and regulator?

  8. That is nor repairing the regulator, that is replacing it. It is also possible to just unsolder the brushes and fit new ones, a lot cheaper than replacing the whole regulator.

    A bad battery will not mess up the brushes, they wear down with time as the are constantly in contact with the rotating sliprings in the alternator. When replacing brushes take a good look at the sliprings, the copper rings in the alternator that the brushes run on,as they can also wear down and can become scored and if that is the case they will cause premature wear on the new brushes.

  9. Thanks a lot, friend. I've been all over the internet looking up the components of an alternator, and I finally stumbled upon your video. My alternator is not producing full charge, and as usual, my mechanic suggested replacing the whole thing. Wouldn't be such a big deal, except that the alternator itself costs 200+ dollars. And my dad suggested it could be as simple as those carbon tips. The thing is that we call them simply as "coals" (we're non-English speakers; my dad doesn't even live here in the States). So, here I was, trying to look up "alternator coals" or "alternator contact tips", trying my best to use the proper English term for it to find results on the internet, and to see if I can buy them online (or which local store may carry it). Anyway, it took me a few hours, but here I am, and I know what I'm looking for. There is a chance that it won't fix the issue, since I'm not sure it's just that, but like you said, and like my dad said (and he's pretty darn good at diagnosing car problems) it is more than likely just the "coals" (as he calls them) – the carbon tips. Also, accessing the alternator on my car is not as easy as on your Porsche. It's a newer (at least compared to your 944) car, a compact FWD with a transversely mounted engine. The alternator is stuck between the block and the firewall with pretty much no clearance. I've watched a video of it's replacement, and it is pretty involved. My mechanic also hinted on the possibility of it being "some work". So, a steep replacement cost is to be expected. Therefore, I'll probably be attempting to replace the carbon tips myself. It sure will cost me time, but with the alternative being an extra 150+ bucks in parts and about that much in labor, I'll take that chance. Thanks very much again. You can't imagine how much you've helped. Now I know the way to tackle my problem AND I've learned a new proper English term 🙂

  10. Hi, my car wont start. When i try to start it there is no responce, no sound… absolutely nothing… When i open the door, i can see warning lamp for open door. I then concluded that there is power, but it may be that i have problems with the voltage? It worked perfectly yesterday, but when i was about to go to the mall today, it just randomly refused to start.

    Please answer, i want to fix it before work on wednesday!

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