Car Alternator Project

[Briggs 2.0]

I am having a complete nightmare trying to get an alternator to work and I'm at the point where I need some pointers before I hit it with a 2lb hammer. It's connected by a drive belt to my diesel motor and there's no slip. All I'm getting is 1volt out of it when it's spinning at around 1500rpm so something is not right. Upping the revs produces a little more but nothing near 14.4v. I always thought alternators produced 14.4v no matter what the revs and more revs meant more amps.

I can't take a photo of the alternator because it not with me at the moment. The alternator is the type with a three pin connector made up of two large blades and one smaller blade connector. There is a negative pick up on the casing. Does anyone have a wiring diagram they can share with me?

Edit: It's not fitted to a car it's attached to a stationary engine so there's no wiring loom, I'm having to wire it from scratch.

[Yorkshire Andy]

Has it been run up without a battery connected? If so Check the bridge rectifier and check its not shoving ac out

To check bridge rectifier de solder one end of each diode and multimeter it it should only beep one way round on diode test setting

[Yorkshire Andy]

http://www.chargerr.com/Alternators/chargcircuit2.gif

[preparedsurrey]

Hi do you have a warning light connected up in the circuit, they won't work without one! Also, check the body is earthed and the connections are good. Either of the big terminals should go to battery positive. The little terminal needs to go via a bulb and a switch to +ve. Obviously the body of the alternator should have a good connection with -ve

They also need a certain amount of revs to kick in and start charging, we put one on an old leyland tractor years ago and you used to have to rev it momentarially right upto the governor before the alternator would start to charge, once it had started though it would continue charging on tickover

[Briggs 2.0]

Thank you for your input, chaps. I've ordered a Euro plug to fit the alternator so I can be sure I've got good contacts. I've moved the engine and alternator away from home so I can apply revs without waking the whole neighbourhood - this will allow me to test properly.

Briggs

[Bongo]

Youre going to need to spin that alternator up to 2000rpm+ to get it generating and like preparedsurrey says once its started then you can cut back on the motor speed.