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Not sure if my alternator is nackered (quick answer please) UPDATE.
Posted: Wed Jan 26, 2022 8:31 pm
by ah
Driving this morning to work the battery light +handbrake+brake lining wear, we’re flickering all at the same time where slowing down and I’ve got home tonight and the battery is not flat but it’s not far off,are these signs of a nackered alternator.
Re: Not sure if my alternator is nackered (quick answer please)
Posted: Wed Jan 26, 2022 9:07 pm
by Contours
Maybe, but would screw out the brushes first in the alternator and see how worn down they are. A flickering light shows intermittent charging so you may hopefully just need a brush set to restore order. Also check if you have a loose or worn fanbelt--that can slip and not spin the alternator pulley sufficiently.
Re: Not sure if my alternator is nackered (quick answer please)
Posted: Thu Jan 27, 2022 9:50 am
by miks15
I had this exact thing a couple of months ago. I put off looking in to it until it was too late...
On my car (318i M40 engine), the bolt holding the alternator tensioner arm to the engine had come loose and therefore the belt loosened off a bit. I only found this out when the bolt actually worked itself out completely and the belt lost all tension. Dash lit up, I thought I could get it home before the battery died, but the coolant temps shot up too since that belt drives the water pump. All fixed now with a new belt and bolt, and I replaced the rubber mounting bushes too for good measure.
Probably worth checking the belt tension and all the bolts are done up nice and tight.
Re: Not sure if my alternator is nackered (quick answer please)
Posted: Thu Jan 27, 2022 6:48 pm
by ah
miks15 wrote: ↑Thu Jan 27, 2022 9:50 am
I had this exact thing a couple of months ago. I put off looking in to it until it was too late...
On my car (318i M40 engine), the bolt holding the alternator tensioner arm to the engine had come loose and therefore the belt loosened off a bit. I only found this out when the bolt actually worked itself out completely and the belt lost all tension. Dash lit up, I thought I could get it home before the battery died, but the coolant temps shot up too since that belt drives the water pump. All fixed now with a new belt and bolt, and I replaced the rubber mounting bushes too for good measure.
Probably worth checking the belt tension and all the bolts are done up nice and tight.
Thanks for the info mate,I took the alternator off last night and the bolts were fine and the belt tension was also fine,I put down to the car being 32 years old and covered 147k on the original Bosch alternator from the factory.
Re: Not sure if my alternator is nackered (quick answer please)
Posted: Thu Jan 27, 2022 9:39 pm
by 30316
Easiest way to check if the alternator is charging is to hook up a voltmeter/DVM and read off the voltage with engine running and not running. You can also get quite cheaply volt meter that plugs into the cigar lighter get the result.
Re: Not sure if my alternator is nackered (quick answer please)
Posted: Fri Jan 28, 2022 2:24 pm
by Contours
Did you remove the brushes from the alternator to see how worn down they are. It's two phillips head screws to get it out to check. You can get new brush sets cheaply enough instead of a new alternator if they are kaput.
Re: Not sure if my alternator is nackered (quick answer please)
Posted: Fri Jan 28, 2022 9:16 pm
by aimlessrock
Contours wrote: ↑Fri Jan 28, 2022 2:24 pm
Did you remove the brushes from the alternator to see how worn down they are. It's two phillips head screws to get it out to check. You can get new brush sets cheaply enough instead of a new alternator if they are kaput.
..as above i removed mine few years back, replaced the brushes (less than £20.00 if i remember) cleaned it up and refitted. worked like a charm.
Re: Not sure if my alternator is nackered (quick answer please)
Posted: Fri Jan 28, 2022 9:39 pm
by ah
O so maybe I’ve spent £120 more than maybe I had to.
Re: Not sure if my alternator is nackered (quick answer please)
Posted: Fri Jan 28, 2022 9:51 pm
by Contours
No such thing as overspending on an e30---the car probably deserves a new alternator anyway.
Re: Not sure if my alternator is nackered (quick answer please) UPDATE.
Posted: Sat Jan 29, 2022 4:36 pm
by ah
I changed the alternator this morning and it’s all sorted.The Bosch original that I took off was a 80 amp I’ve replaced it with a 90 amp,I hope that won’t affect anything,the only reason I changed amps was price.
Re: Not sure if my alternator is nackered (quick answer please) UPDATE.
Posted: Sat Jan 29, 2022 5:21 pm
by martauto
ah wrote: ↑Sat Jan 29, 2022 4:36 pm
I changed the alternator this morning and it’s all sorted.The Bosch original that I took off was a 80 amp I’ve replaced it with a 90 amp,I hope that won’t affect anything,the only reason I changed amps was price.
Nice you have it sorted mate
Mart.