72 Johnson 65hp draining battery

[sgruebs870]

I've got a 1972 Johnson 65hp outboard that drains my marine battery in about one day. I used it all day July 4th, pulled it out of the lake, launched the next morning and the battery was dead. I bought the battery new two days prior and returned the battery thinking it was defective, got a new one and it drained it in one day again. I unhooked all wires for lights and bilge pump thinking it might be that and charged the battery overnight and it happened a third time the following day. What's the deal???? Is it a short somewhere in the internal wiring? I'm not very "outboard savvy" and any help would be greatly appreciated. A close friend of mine has an internal wiring harness and powerpack from a 1972 Evinrude 65hp Triumph that look brand new and are in fine working order he said he would sell to me for $50 if that's the problem.

 

[F_R]

Re: 72 Johnson 65hp draining battery

So, you are saying it drains the battery when it is not being used, right? And you also says it does it with everything but the motor disconected, right? If those statements are both correct, you obviously have a short somewhere in the motor's electrical system. You can locate the short or you can start throwing parts at it.

Leaving the key turned on will drain the battery after a time. The thermal choke draws current.

Most likely your rectifier is shot. Test it.

Otherwise, look for wires frayed and or shorted to ground. Bear in mind that the problem could be in the control and not the motor.