Hot battery terminals

[UNCC Grad]

1989 Mercruiser 3.0L

After charging my starting battery, I tried to crank the engine and it starts the first time. I then shut it down and try to restart and the starter slows down dramatically and fails to crank the engine. The + and - wires to the battery, to the starter and main ground, are extremely hot. I tried an additional battery that is known to be good and the same thing happens.

It sounds like a short somewhere causing the heat to build in the wires so my first step is to clean and/or replace the terminals. What else do I need to check?

 

[Don S]

Re: Hot battery terminals

Loose battery terminals cause that. make them shiny clean, throw the wing nuts away and get some regular nuts and tighten them with a wrench.
Could also be the ends of the cables where they go into the crimp on terminal is corroded. If so, replace the cables.

 

[UNCC Grad]

Re: Hot battery terminals

Don, I cut back the cables and replaced the terminal ends. I'll have to try to see if replacing the wingnuts help.

Could it possibly be the starter? I doubt you recall, but I had forgotten to put my plug in a couple months ago and water got up below the bottom of the starter before I got the water out. I'm just wondering if there could be a short in the starter somewhere and it needs to be rebuilt? I want to pull it as a last resort b/c I just replaced it a couple months ago before flooding the bilge and it's not easy to get out.

 

[Coors]

Re: Hot battery terminals

Bad ground, too?

 

[UNCC Grad]

Re: Hot battery terminals

Bad ground, too?

Yes, bad ground as well. I thought that was odd...

 

[Coors]

Re: Hot battery terminals

normal- humid conditions.

 

[bruceb58]

Re: Hot battery terminals

I'll have to try to see if replacing the wingnuts help.

Get rid of the wingnuts. Use a stainless steel nyloc nut instead.

 

[gooders]

Re: Hot battery terminals

I had same problem hot battery terminals.Be sure wires are in good condition,no doubt you will have done that. However, I had to change my starter as well as it was toast. Result, cold and normal battery terminals. Hope this helps.

 

[UNCC Grad]

Re: Hot battery terminals

I checked all the wires, replaced corroded terminals and checked with 3 seperate batteries with no change in the situation. I pulled the starter and took it to the shop and the armature is fried. Hopefully this will take care of the problem. I'm guessing when I submerded the starter it eventually caused a short and fried the armature.