[Mk2] [NA] BATTERY/ALTERNATOR PROBLEM

[Canopus]

I have a problem with the charging system but am not certain if its the battery of the alternnator. The car is only used at weekends.

Car starts, just, but its clear there is not much life in the battery, which is 5 years old. Once started its fine all day and starts easily.

Generally once going the volt meter reads fine, just under the top mark, but if I turn the ignition on for the first time its much lower about 1/4 down.

The other day when it started the voltmeter showed a good 1/4 down for a few seconds, no belt slip then it suddenly picked up to normal.

After the run about 7 miles I felt the alternatoer and it was too hot to touch, not absolutly burning but deffinatley hot. Also some slight burning smells on occassion but as the alternator is in the rear I can't see how I would smell this in the cockpit. No smell from under the engine cover.

If I put the lights on the voltmeter dips for a fraction of a second then goes back up to normal. Same thing if I operate the electric windows.

I would probably guess the battery is on the way out other than the episode above which leads me to think its the alternator.

Any suggestions?

Thanks

Geoff

[MR!! wren]

the battery is probably shorted out inside slightly, and is really stressing your alternator, i'd change it before you burn the alternator out. it dips when you put the lights on, because it's just more load on the alternator, the fact that the light then pics up shows that the alternator is working it's ass off to keep up (and doing it, so is working ok)

[Scott Barton]

Had a very similar problem a few months ago. Turns out i had a cell gone down in the battery and the alternator was tired as well. Replaced both and now all ok!

[Canopus]

Just by way of an update, Halfords checked the battery and said it was only at 30% efficiency so needed replacing. Since replaced car has started fine and the temperature of the alternator is lower which seems to suggest the battery was the problem.

I still get the voltmeter fluctuation when windows are operated and on initial ignition (not start) its lower than I recall but the trouble id you never recall what the instruments do all the time, only when something goes wrong.

Lets hope its cured. I'll report back if further problems.

Thanks for the replys

G