LUCAS A 127/65

[hurleyjd]

I have Lucas alternator that I believe that when turning the start key there is no a signal for the alternator to start charging. My question is can I run a jumper from the signal terminal to the bat terminal and make the alternator charge. Can this be left in place permanently. I think there is problem in the fire wall connector that prevents the signal wire reaching the alternator.

 

[used red MN]

My question is can I run a jumper from the signal terminal to the bat terminal and make the alternator charge. Can this be left in place permanently.

I don’t know Lucas alternators that well but my guess is no it can’t remain connected because it will likely drain the battery. What is the alternator on? If it is a diesel with a manual shut off it could be powered by a keyed circuit. If they work like a Delco alternator If it is a diesel with an electric solenoid on the pump or a gas powered unit you will need to power it from a dedicated terminal on the key switch like ACC, or you will need a small dash bulb, a resistor or a diode in the feed if you connect it in the ignition circuit so the engine will shut off.

 

[Richard Nixon]

I have Lucas alternator that I believe that when turning the start key there is no a signal for the alternator to start charging. My question is can I run a jumper from the signal terminal to the bat terminal and make the alternator charge. Can this be left in place permanently. I think there is problem in the fire wall connector that prevents the signal wire reaching the alternator.

Lucas has long been known as "The Prince of Darkness". Just say'n.

 

[Not db4600]

Lucas has long been known as "The Prince of Darkness". Just say'n.

Patented the “automatic dimming headlight”.

 

[hurleyjd]

Okay does anyone have any idea as to what alternator might replace the Lucas. Has to have a w tach terminal. I think if one could be had with higher amp it would work better. This is on a 700 Valtra

 

[Gambles]

I think I’m going to let you or someone else do all the legwork, but there are GM alternators with tach drives available. You can Google it, (DuckDuckGo for me), and all kinds of suppliers have it and at a somewhat reasonable price, at least compared to your Lucas.
Again, will it work or does the tach drive turn the right direction? That will take a little research.

 

[hurleyjd]

I think I’m going to let you or someone else do all the legwork, but there are GM alternators with tach drives available. You can Google it, (DuckDuckGo for me), and all kinds of suppliers have it and at a somewhat reasonable price, at least compared to your Lucas.
Again, will it work or does the tach drive turn the right direction? That will take a little research.

I have searched and have not found anything. The tach drive is electrical it shows on the back as the W terminal

 

[Duner Wi]

I have Lucas alternator that I believe that when turning the start key there is no a signal for the alternator to start charging. My question is can I run a jumper from the signal terminal to the bat terminal and make the alternator charge. Can this be left in place permanently. I think there is problem in the fire wall connector that prevents the signal wire reaching the alternator.

You can use a jumper wire to excite alternator but leaving it connected, I wouldn't do that. Determine if wiring is defective by jumping. If it is, a momentary push button switch rather than fixing your existing wiring could work for you.