3.0 Alternator and main wire lead getting smoking hot

[oldgradywhite]

I am a 1995 3.0 lx mercruiser. I took off from from the dock today and noticed the my volt gauge was only in the high 12 volts when I gave the boat a little gas it went up to 13 volts. So I opened the engine compartment and noticed the alternator was so hot it burned my hand and so was the wire coming off of it. I turned the engine off and trolled back to the dock with my trolling motor. All my wires are tight on the back of the alternator. Could this be a bad alternator? What should I look for? I am puzzled?

 

[oldgradywhite]

Re: 3.0 Alternator and main wire lead getting smoking hot

Bump...

 

[Don S]

Re: 3.0 Alternator and main wire lead getting smoking hot

Sounds like a bad alternator to me, take it and have it tested at a real alternator/starter/electric motor shop. Not an auto parts store.
They can probably fix it for a lot less than it would cost to replace it.

 

[cr2k]

Re: 3.0 Alternator and main wire lead getting smoking hot

Alternator should show 13-14v when running. 12v is low.

 

[mark1905]

Re: 3.0 Alternator and main wire lead getting smoking hot

How are alternator cable connections and wires on both sides of the cables? If you're choking the flow due to corroded/bad connections, then you'll build up heat via resistance in the cable and possibly inside the alternator where it's trying to output the juice.

 

[oldgradywhite]

Re: 3.0 Alternator and main wire lead getting smoking hot

All the cables are in good shape I have checked the main wires and leads they look good. I took the boat down to the lake again to run it and see what kind of volts it would pull. It was up to 13 to 13.5 volt depending weather the blower was on. The alternator heated up quickly and so did the wire on the back of the battery. My boat never left the trailer might i add.I tend to agree. The alternator must be on it way out.

 

[bruceb58]

Re: 3.0 Alternator and main wire lead getting smoking hot

Using a meter, measure the voltage at the alternator output and at the battery. They should both read close to the same. If the alternator voltage reads significantly higher, you have a resistive connection somwhere.