How long does alternator/regulator last?

dw · 07-07-2001, 11:06 AM

Any idea how long alternators/regulators (84-89 911) last? Its probably a range , but whats the average?

------------------
DW

89 Targa

Joeaksa · 07-07-2001, 11:33 AM

DW,

You cannot put a hard and fast answer on this one, but it is clearly dependent on several factors.

How much you drive, how much load is on the alternator, do you drive with the A/C or window defrosters on all the time etc? Is the car driven in hot or cold, dusty or normal climates etc...

The alternator in my 85 model 911 made it 16 years and 75k miles. I would think that most units should last at least 10 years and after that should be overhauled. New brushes and a new regulator are not that expensive as long as you stay away from a Porsche dealership.
My overhaul cost $75 at a plain jane alternator overhaul shop and I am very happy with their work.

Hope this helps.

JA

movin · 07-07-2001, 01:17 PM

That's a good question. As a follow-up does belt tension play a role in bearing life? I tend to run the belts at minimum tension in hopes for longer bearing life.

Early_S_Man · 07-07-2001, 02:09 PM

DW,

Those Paris-Rhone alternators have a spotty reputation, at best! I don't really believe there is an 'average' that can be relied upon. Over the '65 thru '89 years, they have probably the worst reputation of all. Changing reality of the 'world economy' and market pressures haven't been kind to reliability issues for elctrical systems on Porsche cars since the early '80s! Just another auto mfr ... these days! And, that wasn't the case when Ferry and his cousin Herr Piech were running things!

------------------
Warren Hall
1973 911S Targa

movin · 07-07-2001, 03:00 PM

Hey Warren,
Will a Bosch unit fit where a Paris-Rhone was? Are the plugs the same? Can you tell which one you have just by looking at it thru the fan?

mwbaum · mwbaum's Garage

My OEM alternator recently went out at 72,000. I replaced it with a Bosch

cds72911 · 07-09-2001, 06:43 AM

Good question - anyone know? Can the Paris Rhone unit be replaced with a Bosch unit? ('79 SC engine.)

Charlie

twin plugged targa · twin plugged targa's Garage

This may warrant a note, that I had a lot of alternator problems which ended up being over clamping of the fan housing making it 'oval'. This caused the fan to rub on the shroud or housing and indicate bad charging.
I ended up replacing the housing which was cracked!.
Of course the mechanic put in a nice expensive new alterantor and then told me it was the fan housing at fault!!.
Beware the less honest Porsche mechanic 'DIY'
Hope this can help someone!
Rgds Ben