Intermittent Alternator Charging Issue

[Guest barksavon]

I seem to have an intermittent problem with my alternator chaging then not charging. Noticed yesterday while out for a run that the battery warning light was 'glowing' then when got home it was on, with alternator not charging. Been back to car this evening and when started it seemed ok and alternator charging. Started it up a bit later seemd fine but when blipped revs to about 3500 battery light came on and no charge, let it run for a bit, blipped it light went out and alternator charging again......obviously an alternator issue, belt okay and alternator pulley spinning fine,anyone any suggestions, is it fixable or do i need a new alternator

[Tazzzzman1]

Had exactly the same issue Oct last year. Altenator light glowing when engine revved, but on tick over all okay. Couldn't pin point the problem until I was towed home coutresy of Mr Green Flag, when I lost all electrics at night in the centre of Sheffield!!

Definately an altenator problem. Mine was charging ok on tick over and lost charge when revved. Sort it now before it Fubars the battery (which happened to me)

 

HTH

[Guest dinger]

Are you just relying on the charge light to tell you the battery isnt being charged or have you measured charge rate at the battery?

[Guest barksavon]

Are you just relying on the charge light to tell you the battery isnt being charged or have you measured charge rate at the battery?

 

No ive got a tester that you put across the battery terminals, if its charging theres 2 lights that come on showing there's 14v going into battery, it corresponds with the warning light coming on

[Guest barksavon]

Had exactly the same issue Oct last year. Altenator light glowing when engine revved, but on tick over all okay. Couldn't pin point the problem until I was towed home coutresy of Mr Green Flag, when I lost all electrics at night in the centre of Sheffield!!

Definately an altenator problem. Mine was charging ok on tick over and lost charge when revved. Sort it now before it Fubars the battery (which happened to me)

 

HTH

 

Terry

did you isolate the actual problem with the alternator or put another one on??

Thanks

ian

[Tazzzzman1]

Terry

did you isolate the actual problem with the alternator or put another one on??

Thanks

ian

 

Did the same as you and checked the charging circuit. Both myself and the Green flag guy came to the same conclusion of a Knackered altenator. Replaced with another one and no issues since.

[Guest mikebloomfield]

No ive got a tester that you put across the battery terminals, if its charging theres 2 lights that come on showing there's 14v going into battery, it corresponds with the warning light coming on

 

just checking..... are you getting 14v with the dash light on? 14v is a good thing, it means the alternator is OK but your dash light is faulty. If you're not getting 14v then the alternator has a problem.

 

have you checked the alternator connector? mine corroded and gave poor charging. Revving the engine could cause vibrations that give an intermittant connection.

 

have you checked the carbon brushes? They wear down, and again revving could cause enough vibration to give a poor contact. The brushes are sprung loaded so maybe the springs are gummed up?

 

HTH

Mike

[Guest Alan_builder]

just checking..... are you getting 14v with the dash light on? 14v is a good thing, it means the alternator is OK but your dash light is faulty. If you're not getting 14v then the alternator has a problem.

 

have you checked the alternator connector? mine corroded and gave poor charging. Revving the engine could cause vibrations that give an intermittant connection.

 

have you checked the carbon brushes? They wear down, and again revving could cause enough vibration to give a poor contact. The brushes are sprung loaded so maybe the springs are gummed up?

 

HTH

Mike

 

Yes Brushes, also take a look at the thermal fuse (its in the Sierra loom) thay can give trouble.

 

 

If your Alternator is near the exhaust they can cook. The cooking also seems to do for the connectors.

 

 

[Guest barksavon]

Thanks guys, changed the carbon brushes and everything working fine, didnt even pay for the brushes as the auto electrician i went to in Belper couldnt find his new ones so gave me some used ones which were better than those i took out.....result