Alternator?

[Shaney23]

Hi Guys,

Can someone tell me if it will do any harm running an alty with no wires connected (Motorcraft).
If it will do damage how can I connect it to what so that it won't??

Regards Shane 351W

[Grease Monkey]

Apparently its a bit of a no-no. Can bugger up the regulator, diodes and winding etc.

Just run a thickish wire from the main connector bolt on the alternator to the battery or to the starter, and from there to the battery before you start the engine.

You'll need to connect coil, starter solenoid etc anyway, so you may as well do one more wire.

[MARTIN123]

No You F--k Up The Regulator Just Give It A Earth On The Field Termial (thats For Your Warning Lamp ) But It Needs This To Open,and A Good Earth To The Engine And Then A GooD Battery Feed Ok

[SimonP]

Martin,
When the alternator starts to charge, the "diode trio" will try to send the field terminal up to 14V. With this shorted to earth, the diodes will be damaged.

Although the alternator relies on about 100mA current into the field via the warning lamp to help it start charging at idle speed, it will likely start to charge at about 3500rpm without the lamp in circuit (or indeed with the field terminal grounded). This is how "single wire" alternators work.

Shane,
Connecting up as Grease Monkey says won't do any harm.
You could also connect up a small (12V 1-2.2W) lamp between the main terminal and field terminal to actually get the alternator to charge. You can then also check it's output.

When stopping the engine, you MUST kill the ignition circuit BEFORE disconnecting the battery, or the alternator will be damaged.

Simon.

[Shaney23]

Thanks for the replies Guys,
Hi Simon how are you? coz I am starting the motor in the chassis for the first time I may be better just running the w/pump with a short belt then I am sure not to do any damage.
Lectrics are deffinatly not my strong point.
Shane 351W