Porsche 911UK Forum

Welcome to the @Porsche911UK website. Register a free account today to become a member! Sign up is quick and easy, then you can view, participate in topics and posts across the site that covers all things Porsche.

Already registered and looking to recovery your account, select 'login in' and then the 'forget your password' option.

996 C4s Battery Generator Fault - Alternator advice

BK911

Well-known member
Joined
16 Mar 2008
Messages
381
Hi guys,

Warning light came on last night.. cars 16 years old and on 56k miles... fair enough :lol:

Any advice? An OEM Porsche one is about £1500!! :floor:

Indie recommended a Bosch one for about £285

https://www.carparts4less.co.uk/alternator

Is it easy ish to do by yourself?

Any advice welcome
Cheers,
BK :thumb:
 
Check your voltage output with engine running, should be 14v ish. If alt failed then remove it and take it to a Starter / Alternator refurb repair shop, they will sort it for a fraction of the prices you have quoted.
 
Cant go wrong with a Bosch one - seems like a fairly decent price.
 
DEFINITELY don't go to OPC!

Take it to a car electrical place and it's most likely to be the voltage regulator that's gone.

About £50 (or £80 if they service the alternator) to fix and the "Pelican 101 projects for your 911" site shows you to get alternator out (quite simple).
 
Watch out for the small print - those Bosch ones are recon models not brand new!

My indie fitted a brand new Bosch which cost him about that, not sure where he got it from. Fitting was about an hours labour, and he put in a new belt too (£36).
 
Thanks guys. All very helpful.

I'll check out the 101 website after work.
 
EGTE said:
DEFINITELY don't go to OPC!

Take it to a car electrical place and it's most likely to be the voltage regulator that's gone.

About £50 (or £80 if they service the alternator) to fix and the "Pelican 101 projects for your 911" site shows you to get alternator out (quite simple).

This would be nice. I'll let you know :thumb:
 
It will be just the voltage regulator but I changed the whole unit as it was 15 years old anyway and it wasn't loads of money in the grand scheme of things.

Easy enough to do yourself but there are a few pitfalls to avoid. First is, it's fiddly to get back in, so can be a real pain - don't lose your temper :lol:

Secondly, there's a small coolant joiner that bolts up just to the right of it. It's very brittle when old. I snapped mine easily when putting stuff back together. Was a kick in the balls. Only 3 quid for a new one. I'd replace it as matter of course. If you don't want to, to avoid an accident just take the bolt out whilst you're working on it.

Last one is there's a brass (?) Bush that the pinch bolt tightens into and pulls it in tight. It needs a crack sometimes to allow the old alternator to come out. Problem is, people have managed to break the lugs on their alternators and that leaves you with a surcharge you can't reclaim.

Good luck.
 
My alternator failed three weeks ago. Took it apart and found that the bushes Were worn away to virtually nothing. 100000K mile car. I replaced it with the new regulator from frazerpart for about 50 quid. Moderately easy DIY
Guy
 
As above - be patient. Buy the little plastic pipe in advance as it will break.

If reinstalling the original alternator, the bushing on the leg at the opposite end to the Pully (the forward one) needs to be pressed back into the leg. As mentioned above it clamps onto the casting in the engine when you tighter the bolt. If you push it back into the leg casting, the alternator will drop back into place. If you don't, you be lucky to get it back in. Use a spare nut and bolt and a socket to 'push" it back in. Don't try to hammer it as the casing cracks easily. Ask me how I know .....

Recommend to change the aux belt while you are at it.

Give your Airbox, maf and butterfly a clean at the same time as they are exposed.
 
Ive literally just posted this in the 997 section ..

deMort said:
One tip .. hitting the bush in the alternator can snap off the bracket that side .. seen it done .. i tend to pry bar the alternator off then ..

Get a socket thats larger than the steel bush but small enough to support the bracket ..

Someone holds the alternator with the socket on the ground and the bush in it.

Then you can beat it as much as you like without fear of the bracket snapping ( put the bolt in and hit that ) as the socket supports the bracket and the bush can move inside the socket .

Refitting the alternator is much easier if the bush has moved back a bit .
 
Thanks for all the advice guys.

Long story short, sourced a new Bosch alternator. Cost £299 incl vat for the part, plus 2 hours labour. Sorted.
 

Attachments

  • img_7684_202.png
    img_7684_202.png
    1.9 MB · Views: 1,759
Ghianightmare said:
Recommend to change the aux belt while you are at it.

Give your Airbox, maf and butterfly a clean at the same time as they are exposed.

Thanks for this.👍🏼
 

Attachments

  • img_7685_982.png
    img_7685_982.png
    1.8 MB · Views: 1,752

New Threads

Forum statistics

Threads
124,357
Messages
1,439,465
Members
48,716
Latest member
993gtnut
Back
Top