Battery Charging Problem

I want to test to see if the alternator on my series 3 diesel is working. The battery completly wears itself out on a 1 hour drive in the dark, even after a overnight charge. Was going to fire the engine and take the battery out and put a volt-meter on the battery terminals to see if I'd get 12 volts. Does anyone know if this is a good idea, or has anyone a more sure fire way of testing to see if the alternator is in good shape?? Talking to one of the lads there and he reckoned disconnecting battery with engine running on a modern car not a good idea, not sure bout a series though??

don't do that;; its a very bad idea.
stick yer multi meter across the battery with injun orf and check yer reading, then start yer engine . yer should have about 13 or 14 volts there. you go much above that and yule folk yer battery , go below it and yer likey as not , not be charging.

Thanks slob - I'll check 'er out in the morning.

It might be worth keeping your eye on;
http://www.landyzone.co.uk/lz/f6/battery-charging-problem-51499.html

I think we may be in the same situation !!

Aye, just checked voltage accross terminals with engine off: 12.4v. Fired er up and then only getting 12.05v so must be a alternator issue. The thing I remembered was that while I was driving round a lot over Christmas the charge light came on and stayed on even with the engine running. It stayed on until about 3 weeks ago and then mysteriously, went out. Also around this time I blew a fuse that controlled the brake lights & indicator. I think all these might be connected, as the battery has been acting up pretty much since the charge light went out.
If anyone has any ideas please me know - thanks, Pat

does yer light come on before yer start the injun?

No, red charge light competly gone now.. Stayed illuminated for probably round 20 hours of driving and then went out, bulb could be cooked now i guess?

remind me, have yer got a lucas ACR alt?

Yeah tis a Lucas alright...

reet i suspect wot yer got is.. the center brush has drilled its way through the slip ring. when this happens your warning light can no longer earth so it will not light before you start up., and as the brush is no longer making contact it will not charge either.

to check take yer alt off and remover the black cover, you'll need some small sockets fer this (5 or 6mm) i think. then remove the brush holder and you'll see the slip ring if it has a hole in the center its fooked.

i once repaired one by filling the hole with some wire and some solder, its lasted till i sold the car and then some.

course it might not be that so make sure you have checked all connections before you go to the bother of removing it

Niceone Slob-would that explain the light staying lit continously for such a long time beforehand though I wonder? Either way will whip alternator off and examine. Are the connections you mention to check the connections to the alternator to battery?

fivepunjab said:

Niceone Slob-would that explain the light staying lit continously for such a long time beforehand though I wonder? Either way will whip alternator off and examine. Are the connections you mention to check the connections to the alternator to battery?

Click to expand...

alt , battery and warning light and any thing else in between including the earths... not sure about why it stayed on fer a long tiime. if they wear through you usually only get a brief flash of it, but yer never know . any way if you check all connections and your sure yer battery and belt are ok then its can only be yer alt

Thanks again Slob, will crack into er tonight and let you know how things proceed..