While fishing this past week everything was running smooth when with no apparent reason engine quit running. Coil was extremely hot! After being towed in replaced coil went back out 45 minutes later same thing again! Now new coil no spark electronic module appears to be no good! What could be causing this mechanic wants to rebuild engine. Never had a coil issue the 4 years I have owned the boat! Engine is a 260hp 350 mercruiser 1984

Id try another coil,,and maybe just do a tune up,cap,rotor plugs,wires.

Does you 1984 ignition have points by any chance ?

BTW: how do you know your coil was bad ? And not the module going out. And what makes you now think the module is bad now but not before ? Basically, asking for what your diagnostics where.

Wait, did I just notice re-reading your mechanic wants to rebuild your engine over a coil issue or did you fail to mention other things ?

there may be no dwell left in the module or its outputting to much voltage.

Mallory electronic ignition replaced coil went fishing again. 45 minutes later no spark again. Took it to a marine mechanic who told me module burned out. He replaced electronic ignition and coil ran 5 minutes back to no spark again. Told me no charge pick it up he don't know what is wrong with it and get it out of his yard. True story!

whats the alternator putting out for voltage?

13

Is it possible you got the wrong replacement coil or you left the key on before running it ?

yes it is possible. I have ordered a replacement distributor with ignition and coil! I will receive it all in a couple days.. I will let you know how things turn out the end of this week!