Hell friends!! Supra beast wiring problem

[darflinger]

Soo- I've had my Supra Beast for about 20 years and have restored it twice,, but have avoided dealing with the decaying wiring...
I've not been getting a charge from the alternator to my batteries, and I think it might be the ballast resistor... Does anyone know how to test? or anyone know the parts so I can just replace???
Also- I have put in electronic points and got rid of the rotor,, if that matters..
Any help would be GREATLY appreciated.. Ive been slowly draining my batteries every time I go out...
Thanks - Brian17141

[michael hunter]

Ballast resistor was part of the original ignition system . Even if it was bad it wound not cause an alternator problem. Have you tested the alternator?

[darflinger]

Alternator tests good (at the alternator)- but I'm only getting 12v up at the batteries. Is the balast resistor buy passed now that I got rid of points?

[chris young]

Most likely culprit is the orange cable from the alternator to the 20A breaker on the engine, or the red wire from the starter relay to the 20A breaker. If all seems ok run a wire directly from the alternator to the battery and see what you get. As for bypassing the ballast resistor, that depends on the electronic ignition type you have. Some need to be bypassed some don't.

[darflinger]

Thanks- I was poking around with my voltmeter- and the farther away from the alternator I get,- the less voltage I read.. Can I run the motor and unplug the harness? or will I fry something?
What minimally needs to be hooked up to run?- I'd like to unplug everything I can, and find out where the power drain is..

[chris young]

If you have good voltage at the alternator, nothing is pulling it down per se. It's almost definitely a bad connection (or multiple bad connections) some where, you don't need to unplug anything to find your problem. Check and clean all the connections in the chain I mentioned in my post above and see what happens. If the first point you check after the alternator (orange cable at the breaker) is lower than the alternator, start with the connections at the alternator and at the breaker. If you have any voltage difference between the two terminals on the breaker then either one or both of those connections is bad, or the breaker itself is bad. If you need to check that, you can move all the wires connected to the breaker to one lug on the breaker, which will bypass the breaker. If this fixes the problem, then you need a new breaker, don't run the boat with the breaker bypassed for normal operation until you get a new one, because if you do have or develop a short, you may get a fire, and fire on boats is bad!

If you PM me your email address I can send you an easy to read wiring diagram that applies more or less to all the older Supras.

[darflinger]

Thanks-- so I ran a wire directly from the alternator to the batteries and the voltage at the batteries is slowly rising , - they are charging- ...
I know my wiring needs to be replace in its entirety(huge job) so until winter, could'nt I just run a wire between the alternator and batteries for a season?