Hi, im after an alternator for my e30 325i motorsport convertible (1990).
please send pictures along with price. could pick up local around beds and herts. alternatively please text or whattsapp me on 07931726035
many thanks
e30 325i alternator required
Moderator: martauto
- Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
What's wrong with the existing one? Most alternator failures are just worn carbon brushes in the regulator pack, and this is easily and cheaply replaced without even removing the alternator.
Hi Brian. the problem i have is the battery sign is constantly on, whether the car is on or off. it drains the battery after 2/3 days and having to jump start the car when required. I took it to a garage locally and was advised to buy an alternator as existing one is apparently knackered. And as to your advise quoted, how easy and cheap is it to replace the faulty alternator. please advise???.
many thanks...foyez
many thanks...foyez
- Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
With those symptoms, then it's more likely to be the diode pack in the alternator that has failed, which is much more difficult to replace, so a fresh alternator is the way to go.
Remove the regulator pack from the rear of your replacement (just two small cross head screws), and compare it with the regulator from your old alternator. Use the one that has the longest carbon brushes.
E30 alternator is easy enough to replace. Disconnect battery negative lead, remove air filter box, and there's plenty of room to disconnect the two wires and remove the bolts.
When you've fitted the replacement, make sure that the nut on the adjuster is only just slack enough to allow the adjuster pinion to be turned. If it is left slack, the pinion will tend to slide down beside the teeth of the rack, and damage them.
Tighten the belt so that you can depress it about 15mm halfway between the two pulleys on the longest run, with light pressure from a finger. Might need checking and tightening again after a few hours use.
Remove the regulator pack from the rear of your replacement (just two small cross head screws), and compare it with the regulator from your old alternator. Use the one that has the longest carbon brushes.
E30 alternator is easy enough to replace. Disconnect battery negative lead, remove air filter box, and there's plenty of room to disconnect the two wires and remove the bolts.
When you've fitted the replacement, make sure that the nut on the adjuster is only just slack enough to allow the adjuster pinion to be turned. If it is left slack, the pinion will tend to slide down beside the teeth of the rack, and damage them.
Tighten the belt so that you can depress it about 15mm halfway between the two pulleys on the longest run, with light pressure from a finger. Might need checking and tightening again after a few hours use.

