Fried battery

[mcbouche]

long story short.. Went to start the motor - a 1987 90hp mercury - and the starter wouldn't work. Asked wife to hold the ignition key in the start position to check for voltage at the starter. Did this to check if the starter selonoid was ok although it was clicking. Before I could get a reading the wife became alarmed at a smoke condition. I did not see anything but it turns out the battery was smoking inside the boat. The wife and I grabbed the key a ran away. Came back in a few minutes and found the battery terminal melted through the battery case. Any thoughts?


Is there an easy way to check if a starter works?

 

[Silvertip]

Re: Fried battery

Yes. Clean and tighten the battery cable connections -- on both ends of both cables.

 

[canoemang]

Re: Fried battery

You could pull the starter and bench test it. The battery melting terminals is not good.. old battery maybe or as said above lose connections may have caused it.

 

[Texasmark]

Re: Fried battery

lose connections may have caused it.

Or corroded.

The heat comes from a mating terminal where there is some resistance. At the current level required to start engines, (100-200 amperes) any resistance is like a resistive type electric space heater. Current through a resistance dissipates power (I squared x R), hence gets hot.

Clean up your terminals, clean and bright and tight, inside primarily where you want metal touching metal after you install your new battery. Get the ones on the battery and the red ones going to your solenoid and starter and don't forget the black ground wire from the starter to the engine block and the black cable to the engine from the battery.

Mark

 

[mcbouche]

Re: Fried battery

No corrosion present - everything is bright and clean. However, some connections seem to be lose so I will have to go over everything to make sure its all tight. The battery was 7 years old, but I dont know if that had anything to do with it, but it doesnt matter now that its trash.

Thanks for replies.