alternator issues

Post by **j_robi** » 24 Nov 2005, 10:28

just wanted to pick your brains
have got concerns that my alternator may be playing up,as have come to the van in the morning several times and the battery has been just dead. when at home the other day we tested th battery for its charge, and it wasnt as high as it should be. (in terms of the starting in early mornings, i have cpvered the battery with blanket and it appears to do the job, it is starting ok with it!).
im guessing when the ignition goes on the red battery light should go on, then when the engine is started the red battery light goes off...? (thats whats happening)
its not just early mornigns that the problem, it had been running fine, then went to stopped at the shop for ten minutes and it was just dead...?
could it be wiring problems o i the alternator dodgy?
cheers

Post by **tonytech** » 24 Nov 2005, 10:46

First up check the connections from battery to Van. Terminals should be bright shiny metal not green or black.
Rub em down, clamp up connectors (not over tight) cover em in vassaline.
Have a look at the engine earths while you are at it.

Charge the battery overnight.
Check battery voltage with engine off (12V ish)
If reading low battery buggered.
Check battery voltage engine running (14.5V ish)
If low alternator not charging propperly or battery taking too much currant.

With engine OFF Remove +ve lead from battery
Connect one lead of a test lamp or an ammeter to the battery +ve connect the other lead to the van battery connector.
Does the lamp light or the meter read a currant if so something is draining your battery.

Keeping the battery warm will increase the power it can deliver.
I'd be wary of keepin it covered as you might trap explosive gasses or accidentaly short out the terminals.

Post by **j_robi** » 24 Nov 2005, 11:01

thanks for that
checked the voltages yesterday. when the battery was off it was very low (cant remember what), when running it was around 12/13v
does that determine whats wrong?

Post by **j_robi** » 24 Nov 2005, 11:38

spoke to a guy yesterday and he said that if i removed the blue wire and earthed it, and the red battery light comes on its an alternator fault, he said that if i eathed the blue wire and didnt get a light it was a bulb/wiring fault...?

Post by **tonytech** » 24 Nov 2005, 11:42

Charge your battery overnight and test again.
12-13V with engine running is a pretty good indicator that the alternator is not putting out charge.
have a look at the back of the alternator and remove the black brush pack.
If the brushes are short ie less than 7mm buy a new pack and see if that helps.

If the brushes are OK you are looking at a new alternator.

T

Post by **j_robi** » 24 Nov 2005, 11:44

ok cheers mate, will let you know how i get on

Post by **Ivorblueun** » 25 Nov 2005, 17:34

if the brushes are ok it could be the voltage regulator which is part of the brush holder assembly and is replaceably at a lot less cost than a whole alternator available from gsf for 9.50 + vat less club discount