Starter melted battery terminal??

[dswi]

1989 Glasstream
Mercruizer 3.0 Alpha one

Bought the boat about 2 months ago. Have been out every weekend since (and love it).
Starter was a little hit and miss. Sometimes it would crank over and sometimes it would not...on the first time.

Went out yesterday and ran for about an hour or 2. Docked at Subway for lunch.
Came back out and boat wouldn't start. Held the ignition switch to the "crank" position and didn't realize it, but the positive battery cable melted in 2 (the lead). Replaced the battery and positive cable. Same thing...got towed to the ramp and trailered the boat in preperation for further troubleshooting in the back yard.
Removed the starter and had it tested at Autozone. Tested bad. It would pull in but would not spin.
A local alternator/starter shop will sell me a rebuilt one for $85-$120.
What could have caused this...and how do I prevent it in the future?
Thanks for input.

 

[Don S]

Re: Starter melted battery terminal??

What could have caused this..

1989 and a wet environment.

 

[Barnacle_Bill]

Re: Starter melted battery terminal??

Also loose and or dirty connections.

 

[Bondo]

Re: Starter melted battery terminal??

Also loose and or dirty connections.

Ayuh,.... The problem started with a dirty corroded positive cable on the battery post, 'n went south from there....

 

[dswi]

Re: Starter melted battery terminal??

Took the starter apart and cleaned the rust/corrosion from the armature/fields. Also used emory cloth on the surface that the brushes ride on. Greased bearings also. Tested and it was fine. Took it to a local starter/alternator shop and the tech there took it apart and said that there was absolutely no reason to replace it...looked good inside.
Put it back on the engine and started...IT NEVER STARTED THIS FAST BEFORE!! Guess I fixed the problem by some simple cleaning. Just for Sh*** and giggles cranked the engine 40-50 times in a row with no faults. It always started within the first second of the starter engaging. Checked the plugs/gaps and points also. Will put a timing light on the engine tomorrow before going skiing.