964/993 owners read this about your alternator.
Discussion
About a week ago I was sat in a pub car park in my 964 and i noticed the charging light very very faintly flickering at tickover, it was barely on so wasn't too worried and it soon went away, then a few days later I was driving along and the abs light and buzzer came on, slightly concerned i continued till I could pull over and stopped the engine and checked the fuse as the radio had also cut out. When I switched the engine off strangely the radio came back on.
Checked fuse all ok.
Restarted car.........Ah battery flat, abs light came on as voltage dropped below abs computer running voltage.
Bump started car and tried to make it home on power left in battery, while thinking I'm sure the engine ecu cut off point will not be far off the abs ecu.
I made it about 5 miles, but luckily stopped right outside a friends house. New mahoosive battery put on and off I trundled, just made it home the ten miles from Bridlington, had it been 15 I wouldn't have, stuck voltmeter on battery and alternator not charging, more astonishingly is the amount of power the engine pulls from the battery, it was dropping 0.1v about every 5 seconds!!! I have done the same in old mg's and an old 2.0 911 and done hundreds of miles on a battery.
So alternator off, not a hard job, set aside about an hour to do the job right taking the blower fan etc off.
Pull out regulator/brush pack, handily it just screws in from the back with 2 screws, no need to dismantle the alternator as on a lot of cars.
New brush pack ordered, cost me under £20.
Refitted and put alternator back in, entire job takes circa 3 hours taking it slow, and costs under £20, now my car has done 130,000miles and is on the original alternator, so I am quite happy at the life of it, but I never even considered it to be something that would go, certainly not as quickly and without warning as it did, bear in mind the non carging light NEVER came on!!! Last year I did a tour of europe in the car and it would have been catastrophic not to mention hugely expensive if this had happened at the side of an autoroute. If your car is getting on it may be worth checking and replacing the brush pack for the effort and time!
It's all sorted and charging at 14.3 volts again now by the way!
Checked fuse all ok.
Restarted car.........Ah battery flat, abs light came on as voltage dropped below abs computer running voltage.
Bump started car and tried to make it home on power left in battery, while thinking I'm sure the engine ecu cut off point will not be far off the abs ecu.
I made it about 5 miles, but luckily stopped right outside a friends house. New mahoosive battery put on and off I trundled, just made it home the ten miles from Bridlington, had it been 15 I wouldn't have, stuck voltmeter on battery and alternator not charging, more astonishingly is the amount of power the engine pulls from the battery, it was dropping 0.1v about every 5 seconds!!! I have done the same in old mg's and an old 2.0 911 and done hundreds of miles on a battery.
So alternator off, not a hard job, set aside about an hour to do the job right taking the blower fan etc off.
Pull out regulator/brush pack, handily it just screws in from the back with 2 screws, no need to dismantle the alternator as on a lot of cars.
New brush pack ordered, cost me under £20.
Refitted and put alternator back in, entire job takes circa 3 hours taking it slow, and costs under £20, now my car has done 130,000miles and is on the original alternator, so I am quite happy at the life of it, but I never even considered it to be something that would go, certainly not as quickly and without warning as it did, bear in mind the non carging light NEVER came on!!! Last year I did a tour of europe in the car and it would have been catastrophic not to mention hugely expensive if this had happened at the side of an autoroute. If your car is getting on it may be worth checking and replacing the brush pack for the effort and time!
It's all sorted and charging at 14.3 volts again now by the way!
loach said:
You sound ridiculously handy. What you described above would have had me by the side of the road pawing at the car and making chimp noises, whilst crossing myself furiously in an effort to ward off the evil spirits that had evidently infested the car.
me too! Nice one Oliver - so you know a little bit about air cooled 911's as well as MG Midgets eh!?
Well I'm not sure OPC sell the brush packs and they certainly won't be the price I paid if they do!
I would very much reccomend anyone with a highish mileage car to get it done, they will go eventually it is a better job to do on the drive way than the motorway!
What I noticed with mone was one of the brushes had worn right down where as the other was ok, so whether that is why the light never came on I don't know?
Next weekend is the clutch, I'm just begining to get a slight slip at 4k when the torque bites, I think it is the slave cylinder so replacing that and the clutch. If I could afford one I would stick a new starter motor at the same time as they are a pig to get too but the clutch job has skinted me, and besides you can always start and drive a car without a starter motor, the alternator isn't like that!
I would very much reccomend anyone with a highish mileage car to get it done, they will go eventually it is a better job to do on the drive way than the motorway!
What I noticed with mone was one of the brushes had worn right down where as the other was ok, so whether that is why the light never came on I don't know?
Next weekend is the clutch, I'm just begining to get a slight slip at 4k when the torque bites, I think it is the slave cylinder so replacing that and the clutch. If I could afford one I would stick a new starter motor at the same time as they are a pig to get too but the clutch job has skinted me, and besides you can always start and drive a car without a starter motor, the alternator isn't like that!
wildoliver said:
i noticed the charging light very very faintly flickering at tickover
Had this on mine last year but had the alternator replaced under warranty, though I didn't realise how bad it could get when it fails totally.
Seems to be a thing with these cars. They are so bulletproof yet often a small thing can leave you stranded. Mine is a 3.2 and has the DME relay which is a common fault and it's what I thought was the problem a month ago when I was left stranded 40 miles from home. Turned out it wasn't to blame though as a crankshaft sensor was the culprit. Again, not something you can do at the side of the road!
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