I have a 2000 Merc 250 XB on a 522 comanche. The positive terminal got hot and burnt off the positive wire. Has anyone ever seen this or know what might cause this? All electrical connections were nice and tight. This happened after days of running the motor with no other issues. Please help.
Pete
Common causes:
-Loose output wire nut
-Corrosion on output wire terminal
-Excessive load on alternator (bad battery, excessive current drains, etc).
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Been there, my trim had a short in it that would cause it to trim up whenever it got ready, if it had been on the down side i would not have seen it happen if on the trailer. Burnt positive and negative off battery before i could get to it. I would look at the trim system first, biggest draw of power i can think of. Would not do it all the time, just when the wires touched. Pump sound ok.
Could be that the voltage regulator stuck closed and alternator staying on above 14 volts overloading the system.
Richard
Took the alternator to an auto electric shop and had it tested, he said that it was probably the nylock nut that backed off and made a loose connection. Too much vibration from lake st. clair. Thanks guys
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