Restoration Wednesday

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Bent, probably on install, top portion.

55 amp alternator pulled apart.

Old vs. new brushes.

Length of wire controls how much spring loaded brush is revealed.


Pulled the wheel finally and found a bent cage around the bearings on the front passenger wheel.  The new bearing should show up today or tomorrow.  In the meantime, I bent it into round the best I could, cleaned everything then packed with new Valvoline synthetic grease.  I still get a hum in the hub, that’s what she said, but it’ll play before it fails or is replaced.

The real rub has been the alternator.  After finding 55amp alternators on eBay, chasing the wrong Valeo new alternators through a local shop and getting/reading different recommendations, I learned this:

• Upgrading to a new 70 amp alternator through say Pelican Parts will require a new voltage regulator, roughly $300 total with core charged.  You may also need to modify/machine your fan shroud to accept the new size.  I’ll pass.

• Rebuilding your alternator will cost about $150-200 at a shop plus shipping.  Eh, what else is out there?

• Rebuilt Bosch alternators are on eBay for about $190-275 plus shipping.  Good solution, no core charge.

• Tearing down your alternator takes a couple hours.  New bearings and brushes were $25 bucks.  Ding ding ding.  Winner winner chicken dinner.

Side notes:
• Kurt at PartsKlassik is a brilliant source for parts and information.  Kurt is a factory trained Porsche mechanic, having served a four year apprenticeship with Scuderia Veloce Motors. Kurt was awarded the Porsche Second Year Apprentice of the Year after completing the Porsche factory training programs for engines, transaxles, and body controls, as well as the electrical, braking, and suspension systems, in 1990. Today, he has over 20 years in Porsche experience and more than 15 years in running his own shop.

• The Porsche dealer will rip you a new one for the same equipment at $580 for the alternator plus $140 core charge or thereabouts.


If you recall from previous Restoration Wednesdays, I started this process because of a metallic sound emanating from the fan.  The diagnosis was alternator bearings.  Now that I’ve rebuilt the alt and installed a different fan and shroud previously powder coated to match the valve covers, I’m happy to say – it fixed nothing.  I fired it up last night about 10PM to the same clanging sound.  The fan doesn’t hit the outer shroud but it must be nicking the back or something.  There was no interference on build or install.  I think cranking down the fan belt may have created the sound.  I also think the alternator shaft may be bent.  Today, back at it as time allows.   

UPDATE:  I couldn’t see the marks in the fan shroud last night but it appears the fan is nicking the shroud creating the noise.  Bent shaft which is a bummer after all that work but at least I’m confident about driving it.  

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