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Old 09-15-2010, 09:32 PM
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supradupe supradupe is offline
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Location: IL und CH
Join Date: Jun 2006
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Mein Auto: 03' e39
Originally Posted by cn90 View Post

4. New Voltage Regulator (a.k.a = "Rectifier")
- Here is the kicker: if checked OK, most simply re-use it but read on.... Although this is a solid-state device (no moving part), it is rated at let's say 2 million cycles of alternator revolutions, then the solid state device just fails any time after that.
- The reason most rebuilders re-use the Voltage Regulator is cost (a good Voltage Regulator costs some $50-60/each).
- This is also the reason why many people run to Autozone, get a rebuilt Bosch Alternator, only to find out 1 month later the Voltage Regulator failed! Some in this forum have gone through 3 Alternators in a 6-month span. What a waste of time and effort!!!

So unless you know exactly how a rebuilt Alternator was performed, rebuild the Alternator yourself for $60.

the voltage regulator and rectifiers are two separate things. the voltage regulator has the carbon brushes and costs 50-60 like you said. The rectifiers on the other hand, is very difficult to source. I was not able to find suitable rectifiers for my bosch alternator and there is a lot of heavy soldering and desoldering to do if one wants to replace the rectifiers. I had rebulit mine only to find out 6 months later that the rectifiers are dead. So, going with your logic, rebuilding yourself can also be a waste of time and effort. At least if one buys a remannufactured alternator, one can get limited life time warranty and get it replaced. Rebuilding on your own, those parts are warranted only for 1 year at most and you are still stuck with a POS.
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