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Discussion Starter #1
My vehicle is a 2009 Boxster (base).
This is my 3rd summer owning the vehicle.

I recently replaced the battery, as the old battery (3 years old) was leaking.

It was suggested I check the voltage at the battery.

With the new battery and engine running (idle) voltage is at 16.2 volts.
It actually was at 15.8..and slowly keeps creeping up from there, it seems to be stopping at 16.2 and then going up or down a few tenths.

1) Do you think this warrants removal of the alternator.

2) If I need to remove it, can a parts shop (NAPA or other) test the alternator to determine if it is the voltage regulator or the alternator itself ?

3) How big of a job is it to remove and replace the alternator in a 987.2 ?

I have watched some YouTube videos, one person said it was a 4 hour job to get the one of two bolts off the alternator.
His directions were to turn the right bolt out 3 turns and hit it with a drift (or similar) and hammer.

I printed out some very nice directions from the 986Forum, the person that created them said it is about a 45 min job to remove the alternator from his 986.

Thank-you in advance,
Tom
mid-Michigan
 

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Discussion Starter #3
Hi Zuch,

I appreciate you checking the manual.

Thank-you for the answer back... fingers crossed I can somehow getaway without having to lower the engine.

I wonder if it would be worth while for me to stop by the Porsche Dealership and ask a mechanic, they seem to be fairly nice people to the DIY and Porsche enthusiast.
 

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Just for reference, when I had my alternator replaced under warranty a couple years ago, they charged $535 for labor (and $1136 in parts). There's no hour breakdown, just a "Units: 3.50".
 

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No idea how low you have to go with the engine but when I replaced my motor mount on my 987.2 it was just 4 bolts very easy to access to lower the engine a couple inches. A block of wood and a jack under the pan and the engine will slowly come down some.
 

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Yeah, it is only 4 bolts and you only need 5cm so a jack and some blocking under the pan is all you need (for that part of the job). Apparently you don't even lower it enough to come off the bolts.
 

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Just as an FYI, there's a TSB from 2010 titled "Charging System - Unnecessary Alternator Replacement". It states that "As of model year 2007, the generator has a charge voltage of between 12.0 and 16.0 V and must be evaluated as functioning correctly in this range."

Apparently it'll throw codes for overvoltage or undervoltage, and if you're not seeing codes it's okay. I'm used to older cars and 16V seems awfully high to me too, but that's what Porsche says. So maybe you don't actually have a problem?
 

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Discussion Starter #9 (Edited)
Hi GUBI, that would be remarkably good news.

My thoughts were, 16 volts is high and I was fearful I might damage some of the sensitive electronics in the vehicle... not to mention the battery. It is Great to know that over charging would provide a service code.

Zuch and Oachs83, thank-you for the heads up on 4 bolts to lower the motor about 5cm or about 6 inches.

Thank-you,
Tom
 

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Your Alt seems to be doing what is was designed to do, if you voltage keeps going above the 16v mark you may check out the voltage regulator.
 
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