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DISCUSSION => General Topics => Topic started by: ClayW on July 06, 2011, 09:57:58 AM

Title: Alternator Source?
Post by: ClayW on July 06, 2011, 09:57:58 AM

I'm convinced that my alternator is dead or dying. Where is the best place for a new one? Are there any other models that use the same alternator?

So far, I'm looking at this one:

$128.44, including shipping

(http://i.ebayimg.com/00/$(KGrHqYOKocE12NvzmgrBNjCtKpG8w~~_12.JPG) (http://cgi.ebay.com/ebaymotors/BMW-ALTERNATOR-BOSCH-120-AMP-318I-318IS-1991-1992-1993-_W0QQcmdZViewItemQQfitsZYearQ3a1991Q7cMakeQ3aBMWQ7cModelQ3a318isQQhashZitem53e7ed5363QQitemZ360373375843QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories)

Of course, the one above begs the question: Is 120A too much? I suppose that I could always install a small, on-board welder.....

Title: Alternator Source?
Post by: DesktopDave on July 06, 2011, 10:59:24 AM

Do you have an alternator/starter shop near by?  They'd know exactly what to do.  They're excellent at testing as well.

I had one down the road that unfortunately closed last year.  I'm not sure what I'll do next time I have a bad alternator.  I sent a buddy there last time; a rebuilt Vanagon alternator is unreal money.  20 minutes & $20 later it works perfectly.

Title: Alternator Source?
Post by: monty23psk on July 06, 2011, 12:19:59 PM

If you have an Autozone near you, you can have it tested for free to confirm. Most of the time, the voltage regulator is what needs replacing. I have my old alternator if you want it, only issue is the hole for the bottom bracket turned into an oval from the bolt being loose. It worked great just caused belt to squeal due to mis alignment. Sure you can swap the housing with yours.

Title: Alternator Source?
Post by: ClayW on July 07, 2011, 02:57:44 PM

I'll take it. Email me at clay dot weiland at gmail dot com and I'll paypal you the shipping. Thanks!

Title: Alternator Source?
Post by: monty23psk on July 07, 2011, 07:35:38 PM

email sent.

Title: Alternator Source?
Post by: monty23psk on July 09, 2011, 03:22:23 PM

Shipped.

Title: Alternator Source?
Post by: rjcaptsean on July 10, 2011, 09:36:23 AM

I love it when we all play well in the sandbox together!

Title: Alternator Source?
Post by: monko141 on July 10, 2011, 10:29:04 AM

Clay, what is the link to the 120a alternator?

Title: Alternator Source?
Post by: ClayW on July 14, 2011, 10:38:01 AM

http://cgi.ebay.com/ebaymotors/BMW-ALTERNATOR-BOSCH-120-AMP-318I-318IS-1991-1992-1993-_W0QQcmdZViewItemQQfitsZMakeQ3aBMWQ7cModelQ3a318isQ7cYearQ3a1991QQhashZitem1e65204630QQitemZ130545632816QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories#ht_1228wt_890 (http://cgi.ebay.com/ebaymotors/BMW-ALTERNATOR-BOSCH-120-AMP-318I-318IS-1991-1992-1993-_W0QQcmdZViewItemQQfitsZMakeQ3aBMWQ7cModelQ3a318isQ7cYearQ3a1991QQhashZitem1e65204630QQitemZ130545632816QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories#ht_1228wt_890)

I've bought from these guys before. They sell a lot and have a good reputation.

Title: Alternator Source?
Post by: DesktopDave on July 14, 2011, 05:50:00 PM

Does anyone know if the 120amp is harder on gas?  I've seen a lot about less amps causing less drag making for better mileage.  But the headroom is a good thing to have.

Title: Alternator Source?
Post by: ClayW on July 16, 2011, 12:16:43 PM

I wouldn't think so. As I understand it, the mechanical draw doesn't occur until the electrical load is applied. The 120A rating is the limit, not the constant.

Title: Alternator Source?
Post by: DesktopDave on July 16, 2011, 12:26:16 PM

Yeah, that's my understanding too.  I think the load tends to be much higher with high-output alts but for shorter periods.  Makes me wonder about efficiency.  From the little I know about it, electrical power draws in a car sacrifice ~10% power.  I'm trying to cut that down without resorting to under-driven pulleys.

Personally I try to keep my battery charged to 100% all the time.  I know it really helps battery life and I suspect it helps fuel mileage as well.  A few more miles if the alt dies wouldn't hurt either.

I might wire a pigtail up permanently...my new Xtreme Charge (http://www.xtremechargers.com/) seems like a pretty nice little unit, works well so far even on AGM and VRLA batteries.  The "de-sulfation" stuff seems a bit far-fetched but so far it's a nicely self-contained and durable unit.