Hi guys does anyone know where a can get a smaller alternator as when the engine is running the charging light is on but if you speed up the revs the light goes off

It's for a pinto engine with a cortina alternator I think but not sure


Thanks

I would say you're treating the symptoms rather than the cause. Are you sure the alternator is a good'un?

Start by checking 2 things (1) Drive belt is the correct width and angle tight enough and gripping on the V surfaces not bottoming out on the pulleys. (2) Take the plug off the back of the aternator, remove the black plastic cover on the alternator and clean the Lucar blade connectors with emmery board and check the female spades are making good metal to metal contact.


If then above are OK then try a new set of brushes -- usually less than £4.00 dead simple to fit, if that dosen't work and new slip ring and regulator and if that dosen't work a diode pack. All easy and cheap to find off ebay

see this http://www.youtube.com/watch?v=wNCnJm92lnY

Alt is deffo a good one its brand new less than a month old it charges okay when slightly revved just the light is borderline on switching off the belt is nice and tight and is driving on the sides of the belt and not bottoming out and it's spinning fine like I said it's brand new but I have to give the old one back to the motor factors so can't even measure it compaired to new one

flakmonkey can make you a nice pulley

Pulley isn't the problem, either a duff unit or arcing at the rear connector the latter scenario used to come up quite often in the heyday of the Lucas ACR series, a new alternator would be bought to replace a duff unit and the new alternator would apparently go belly up after a couple of weeks, cause was knackered spade connectors on the plug.

Its normally a pulley ratio thing rather than necesarily a fault with the alternator. Unless it was working fine and now its not. Especially on an installation where the pulley ratios are not as originally intended by the manufacturer. Ie a smaller crank pulley or bigger alternator pulley.

Most alternators need to spin up to at least 1800rpm to start charging or to kick the coil into action. Once its started charging it then carries on once the revs drop. My pinto always did the same when you first started it. Blip the throttle and it started charging.

As long as you dont exceed the max RPM on the alternator then all will be OK.

[Edited on 5/10/11 by flak monkey]