IH 784 Alternator wiring?

[gatordog]

I have the Lucas alternator and it tested OK. The problem is it is not charging on the tractor. The guy testing the ALT said that the small terminal was the ground and the 2 larger terminals were positive. I have the 2 large terminals (on back on the ALT) wired to the positive side of the battery, and the ground is good. My question is, can anybody confirm the proper wiring for this alt. FYI, the factory wires were all cut and the alt was not hooked up when I got it.

 

[cyrush]

Hi again!!

Do you know which model of "Lucas" alternator is fitted, as they produced severa l types??

 

[gatordog]

The book says it is a Lucas No. 15 ACR and it should have a 3 wire plug on the back and it also has what looks like a lug on the side, but don't know if this lug needs to be grounded.

 

[cyrush]

This should solve your problem !!

If you need the special moulded plug + terminals you should be able to get it at local auto electricians for around $7 to $10 !!

 

[gatordog]

Thanks, I tried every auto part store and no luck with the plug. It was funny since I searched for the plug and found it on the Car Quest web page, but they were unable to get the plug. I have the 2 large spade terminals hooked to the battery. Maybe I need to disconnect the small male spade terminal since the factory dash is gone. I just fitted after marker gauges.

 

[cyrush]

You still need the warning light wire connected to excite the alternator when the ignition is switched on. Wiring it to the 2 large terminals will leave it permanently excited and if the tractor is not used for a period could cause the battery to drain, resulting in not being able to start!!!

 

[gatordog]

So the warning light wire is a positive connection? I have it wired to ground.

If so, I can run it to the ignition switch and see what happens.

FYI. I disconnect the battery when not used.