Hot wire on alternator
 

Hi everyone,

I've just replaced a faulty alternator on my shabah 180SE with 4.3 Merc. I replaced it with the original Mando model. But increased it to a 65A from the 55A that it had. My concern is the orange output wire gets hot especially right after start up. Also, I've noticed it's hooter closest to the terminal. Should I be concerned?Should I replace the wire with a higher gauge wire?

Thanks for your help!!!

Re: Hot wire on alternator
 

Is it consistently hot or just when starting? That orange wire should be 4AWG. Look once at your orange wire again and see what the max amp rating is. It should be printed along the length of the wire (take magnifying glass if your eyes are not that good like mine). Also make sure all your grounds around the battery and the alternator(engine block) are solid I.E. no corrosion, frayed wires, tight, etc...
I am not sure of the connection of the starting circuit and the charging circuit. In my mind they are two separate circuits and should not interfere with each other. Seems strange.
Are you running anything in between the alternator and the battery like an isolator, battery switch, etc...?

Re: Hot wire on alternator
 

I had (am having) the same problem. But mine is no where near a 4awg from the factory. It's probably a 10awg. I installed a MASSIVE battery and larger alternator. Upgraded to an 8awg hot wire which seemed to help some, but I still get a bad smell from the wire getting hot if the batteries are a little low (I run an air conditioning unit). Probably going to upgrade to a 4 gauge to see if that solves the problem. Upgrade your charge wire, and keep your batteries topped off with a charger when possible. Should solve your problem.

Re: Hot wire on alternator
 

I'll most likely change my wire this weekend. But I'm curious as to why it is wired to the starter positive terminal instead of straight to one of the batteries. Except maybe because the engine is purchased as a unit. Would it be better to wire it to either the engine or house battery?

Re: Hot wire on alternator
 

If you wire it to the house battery, you will lose functionality of your battery switch because you will not be able to "turn off" the house battery. I would take it back to the starter.