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Discussion Starter #1
Watched a video on the rebuild of an early, most likely a 70's alternator and it looked like a pretty straight forward process mostly involved cleaning the old unit really well and replacing only a couple of items. Some what labor intensive but not excessive and kind of looked like fun. Has anyone in the community rebuilt a unit and typically what parts need to be replaced during the process, and where is the best place to find those parts. See attached video .https://www.youtube.com/watch?v=lE0_UmFpPUQ

Thanks, Carl
 

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Detritus Maximus
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You might check with a local alternator/starter repair/rebuild place, if you have one. Most of the parts should be standard Bosch or Delco Remy items (depending on which one you have). The area where the brushes ride may need some expert attention. Checking for defects in the windings and other than that, bearings, brushes and diodes. Getting the case apart might be tricky. Sometimes the bolts/screws seize and can shear off due to their length allowing them to twist before you even realize that is what they are doing.
 
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I have a chrome Denso Alternator in my GT. I got it because it was chrome, but more importantly it is about 3/4 the size of the Opel alternator. I believe I paid $85.00 for it on Amazon, probably more than that now. It is smaller than the original alternator and it produces 80 amps. I didn't hook it up to the alternator gauge, because I didn't want it to catch fire. That was three years ago and it has never let me down. I think I would rather buy a new alternator thn try to "overhaul" the original alternator. More juice, no problems, that's what I like.

Bob
 

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Opel Rallier since 1977
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Yes, I have done so. Much of it is straightforward, like replacing bearings.

But some parts of the process take special tools, and specific knowledge of what you are doing and looking for. The electrical work has several steps; you have to unsolder the connections to one side of each diode to test each diode, and then testing the windings. And then sometimes you have to replace diodes, and in some/most alternators that requires a BIG soldering iron with a high wattage rating and some bulk for large heat capacity. You won't get the diode soldering done with a pencil soldering iron; a small butane micro torch might do the job, but I have not tried that. Something like this will work, with a several hundred watt rating; you might find a similar high wattage iron on eBay: Buy Soldering Accessories - Sign In: Free Shipping $50+ | Zoro.com

Then you need the right solder which will probably be a 60/40 or 63/37 solder with rosin core. (The numbers are the % ratio of lead to tin.) Having soldering experience is important, as controlling the heat input to the diodes when you solder to them is important to avoid damaging them.

And if you need the diodes, then you have to find a source for them; that is not nearly as easy as it used to be, as local rebuilding shops dry up.

One thing that the home auto hobbiest will not have is the right equipment to properly measure the very low winding resistances. So all you can do check the individual winding resistances end-to-end using certain techniques with a standard ohmeter, and see if there are any shorts between windings or the case or rotor core; this is to find gross problems in the windings.

This Opel alternator is one of the few I would consider rebuilding if I wanted an original item but all the challenges discussed above of doing it well at home will apply. I have most of the special tools but would still have to find the diodes or complete diode assembly; I suspect the diodes are one major problem with Will's alternator. I would probably just go to OGTS, as they have worked over the years to find good sources for their parts. For most of us, it is well worth the higher price to benefit from their diligence to set up good parts sources.

BTW, the '71 FSM has a complete procedure written up for alternator rebuilding. Back at that time, it was not unusual at all for garages of all levels to do this type of work.

P.S.: Lindsay's video misses a lot of this....but it does show the larger soldering iron typically needed.
 

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Opeler
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For those of us without welding equipment, previously sugguested universal alternator mounting kit.
Search A200 alternator bracket. This is an erector set style assortment of brackets and hardware to convert from generator to an alternator.


Universal Alternator Mounting Kit.jpg
 

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Opeler
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If it were me, I’d rather just spend the money to get it done right and move on....either by having a shop do it or just buy a new one.

But, good luck if this is the path you choose!
 

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Discussion Starter #8
OK it was just a thought - I am going to purchase a new one ..Thanks to everyone for taking the time to point me in the right direction especially Manta Rallier - after reading all of that there is involved with the process no question that it is a lot more work/frustration/chance for failure than it is worth. That video just made it look easy. Lesson learned.:rolleyes:
 

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Two weeks ago I rebuilt the Chrysler alternator on my Dart; first time I've ever taken an alternator apart. My ammeter was slightly discharging at idle but picked up a bit at higher rpm's so I figured there wasn't major damage. I tested the stator for continuity and replaced both brushes, cleaned up all the contact points. For $11 including shipping from Rock Auto, the alternator charges again.
I've never taken an Opel alt apart so I can't compare the complexities.
One of the reasons I rebuilt the alternator myself is because of all the negative feedback on the Mopar forums about the poor quality of reman alternators these days. Now I trust Gil at OGTS much more than AZ or O'Reillys so that factors into the decision too. But if the alternator on Maria's GT ever failed I would probably attempt to rebuild it too just for the experience.
 

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If you change your mind, or anyone wants to rebuild one, here is a site with Bosch alternator diode bridges:

Thanks for the link; I'm bookmarking it. Here's another site:
 

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Opel Rallier since 1977
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I half-rebuilt the alternator in my '62 Dodge (see the avatar background) because I wanted to keep it 100% original. But it was charging right before, so this was really only for new bearings and field brushes. I did not test the diodes like in a full proper rebuild.
 

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The chrome alternator on the GT was put in in 2005. I looked on Amazon (where I got it), and they said it was unavailable and they didn't know when it it would be back in stock. There are another 3 chrome alternators that were Denso style. They were all one wire alternators. the lowest price was $114.00 with free shipping. Like I said mine went on the GT in 2005. For $114.00 I think I would get one of these instead of trying to rebuild the original. The Denso alternator is about 3/4 the size of the original, so it fits better than the original. Just my two cents worth.

Bob
 
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