Strange Alternator Problem

[bonnietiler750]

As it says in the title

I get 13+ on the volunteer then it drops to 11.5 the ignition light never comes on, then it returns..but remains at the lower level most of the time, any ideas it has a decent 12 month old Yuasa battery

[bonnietiler750]

That should read Voltmeter rather than Volunteer...ahem

[StagJonno]

What is it that's returning - the warning light or the voltmeter? Are you measuring at the battery?

Could be a dodgy Ign Warning bulb or loose connection, either external or internal to the alternator. Suggest you check out external wiring first. The small wire connection to the alternator is the Ign Warning connection which also acts to provide initial excitation to the alternator when starting up. Tempoarily removing this and touching it to earth with the ignition on should cause the Ign Warning to light. If it doesn't, this indicates either a blown bulb or it may have become loose in the cluster.

If it lights when tested, then check other alternator connections including the other ends.for security or wire fracture. These are live to battery, so take care not to short circuit.

Jonno

[DJT]

I’m sure someone with more electrical knowledge than I will be along soon, but it seems to me that the alternator could be on its way out. After having two “new” alternators fail on me just outside their warranty period, I bought new regulator and rectifiers and replaced them myself. Easy job and still working fine well over a year and 4,000 miles later.

Jonno beat me to a reply..........

[bonnietiler750]

Yes, just to qualify, my original post probably wasn't clear...not for the first time.. the red ignition operates correctly, but is reluctant to go out first thing (I use the car every day all year round) the voltmeter takes quite a while 30seconds or so to get around to 12 or 13 on the voltmeter if i give it a bit of revs and it the warning light will extinguish the alternator then v..e..r..y slowly makes its way to 13+ volts on the volt meter, this can drop at any time to 11+ but the ignition light rarely comes on on the Warning lights w

[Phil S]

check across the battery terminals with a meter, you should get 13.7v with the engine running and over 12.5v when you stop it, voltmeter can be unreliable.

[Seaking]

This was my trouble brushed came apart. On!y 8200 miles on the alternator