alternator output voltage

[FunkyGibbon]

Just had a battery die on me (totally fooked - despite the use of an accumate!).

Anyhow, got a new battery fitted by Kwik Fit who to be fair were excellent - and cheap £50 fitted.

I got the alternator output checked to see if that was the root cause:

Under full load (lights, heater on) we were seeing 13.6V - seems a bit low, I seem to remember 14.4V being the magic number.

Does it sound like the alternator is on its way out? (It is only 2 years old).

TIA

FG

[that daddy]

That is a tad low,but it depends on the gear your using and the present charge state of your battery,its not far off the mark though.

[GreenV8S]

Sounds fine to me.

[miketvr]

13.6V at the battery is OK - would be better marginally nearer 14V. If you check the voltage directly at the alternator you should see between 13.95 and 14.45V. I know because I re-wrote the Lucas alternator test spec many years ago and was involved in the design of the A127 alternator fitted to the Chimaera.

You always get a bit of a volt drop on the cables when the current is high hence the slightly lower voltage at the battery. By spanning the meter between the alternator chassis and the -ve terminal on the battery you can check to see how much of the volt drop is due to the various chassis connections in the chain.

Hope this helps
Mike

[FunkyGibbon]

cheers folks - I'll test the voltage at the alternator.

FG

[spend]

<14.4v is the magic number - else regulator is suspect. 13v with everything loaded is pretty good.

Dave