Battery Warning Light

[Roadside]

Hi,

Vauxhall Corsa, 1993 1.5 Deisel.

Just as I pulled up in traffic by work this morning the battery light lit up on the dash board. When I pulled away it went off, slowed down in traffic and it came on again.

Power seems normal, idle normal, plus the battery is fairly new.

The oil level is slightly ABOVE the limit (overfill - oops) - I don't know if that affects anything.

Anything I need to do - or should be aware of? A bit concerned that a breakdown is around the corner or I'm doing damage to the car by driving it.

Thanks for any help.

[rivolette]

Sounds like your alternator is on its last legs. When you're stopped (idling) the engine RPM is not high enough for the alternator to generate enough power to feed the system, so the idiot light on your dash lights up.

But when you pull away and feed some speed to the engine, the power generated by the alternator goes up an so the idiot light on the dash goes off.

In my opinion, start by having your alternator inspected. You may have the option of getting an alternator "rebuild kit" (cheaper) or may have to buy a new alternator (more expensive but also more reliable). Also if the voltage regulator in that model year, is outside the alternator (some models have the voltage regulator built right into the alternator), have it checked as well.

As far as the oil being overfilled, I don't see how it could affect the battery warning light, but you're better off to cyphon some oil out of the engine and bring it back to the recommended level.

Best of luck.

[rivolette]

Oh by the way...

One more thing you want to check, is the belt tension. If the belt that drives the alternator, is out of whack, it may also cause the symptoms that you described...

[Roadside]

Yes - I've done some homework this morning and the alternator seems to be the main suspect - I'll take your advice and get it looked at.

As soon as I find out where the sump plug is located I'll drain some oil out as well - from my homework it seems to be increasing the pressure in the engine and running the risk of blowing the oil seals.

Thanks rivolette.

[Roadside]

Just been quoted £162 for an alternator plus fitting!

I think I'll take a look at tightening the belt first - much cheaper...

[rivolette]

160 pounds is not so bad actually. I'm assuming it includes parts and labor, sounds ok to me!!!

Good luck with that. The thing about having a brand new alternator installed, is that you won't have to think about it for a long time to come.

Regards

[Roadside]

I've been looking a bit more into this - are there any pitfalls in buying a reconditioned alternator and fitting it myself.

It appears to just be a few bolts - is there anything I need to be aware of when fitting?

Thanks.

[rivolette]

The most important thing is the torque that you have to apply to the belt when you are tightening the alternator. There should be instructions with the alternator on how much torque you apply to it.

It would be best if you let a professional do this for you, if you want to do it yourself, try and pick up a "torque wrench" which indicates the torque as you tighten the alternator.

Also make sure you note the EXACT path that the belt follows around those pulleys. If you install the belt wrong, you're liable to thrash the alternator.

Again I can't stress enough on the torque that you should apply to the alternator while installing it. Too little torque will cause the same problem you have now. Too much torque will thrash the bearings inside the altenator and it will be useless.

Be extremely careful if you do this yourself.

Good luck... ;)