went out last night had to be towed back!!! put new battery on today seemed to be charging fine but been out again tonight and it's died on me again, could this be a duff alternetor, battery is an 085 escort/sierra. anyone any ideas????

or rectifier!

how much am i looking at for an alternator i'm new to this bike engined business! seemed to be charging ok earlier!!!after a while it starts misfiring then cuts out completely

Sounds like you aren't charging to me.

Do you have anything to test it with? It sounds like your alternator or rectifier as posted above.

Charge your battery up. (Suppose you've done that now) then start the car. With the volt meter straight across the battery the reading should be 14 volts or there abouts.

If not you have a charging problem. Could be any one of the above. Sorry can't remember specifics of checking rectifier / alternator seperately.

One thing you could do is take the alternator into Lucas. They used to check them for free on the bench. That way they had you for a new one if it was faulty.

Hi
There sould be 3 yellow wires coming from the alty, going to your regulator. The regulator has 5 connections, the 3 yellow wires go (in any order) across the top, and the bottom 2 terminals should be your 12v out. The rectifier gets hot and can burn out very easily. Make sure it is mounted on a big lump of ally to absorb the heat and if possible have a good airflow over it. So see if its burnt out try measuring the 12v out of the rectifier.

thanks, located one at a breakers so if its not i can get one for thirty quid!

put a new rectifier on still gets really hot quickly and doesn't show anywhere near 12v. any sugestions

Oh Dear, sounds like one of the coils in the alty may have failed.
To check, pull out the 3 yellow wires from the regulator, and check the resistance between them all, there should be very little as you will just be measuring down a long copper wire, if it is open circuit the then that coil has gone. Then measure between all 3 wires and ground on the engine case, this should be open and no connection, if you measure a low resistance then the insulation on the coil has failed and is shorting to ground and this would make the regulator get very hot. Your case you may find that it only shorts to ground at a certain position, so put your meter on and then rotate the crank. (dont turn the key or yourll blow your meter!!)

HTH

Don't mess about, for what it costs, get a new one!
Cheers J&J

hi berwyn,
done the checks you suggested and everything seems ok, coils are fine!so must be another duff rectifier thanks