battery hooked up backwards

[bodbo]

i have a 55hp evinrude 1978 model. i started having trouble last year after i accidentally hooked a new battery up backwards. before i realized that it was hooked up incorrectly the boat would run fine about 3 quarter throttle but full throttle it would shut down like it was flooding out. the rectifier burnt out and then the main fuse started blowing. then i hooked the battery up right and bought a new rectifier and know the fuse has stopped blowing. my question is can the battery being hooked up incorrectly cause the motor to run like i explained. some one told me no but i think they may be wrong. someone please help. thanks

 

[MCM]

Re: battery hooked up backwards

I seriously doubt the motor would have started let alone run with the polarity crossed from the battery, for one thing there would have been no + current going to the solenoid or starter motor.<br /><br />The battery hooked up incorrectly would most definately have fried the rectifier though, then the bad rectifier would eventually damage the stator.

 

[Joe Reeves]

Re: battery hooked up backwards

If before you hooked the battery up wrong, the engine had sat without running for some time, that would most likely have resulted in fouled, clogged, gummed carburetors. Carburetors in that condition would cause the engine to bog out at the higher rpms or when attempting to obtain the higher rpms.

 

[byacey]

Re: battery hooked up backwards

I'm not familiar with this model, but does it have electronic ignition? The solenoid and starter doesn't care what the polarity is unless the starter has a permanent magnet field, but the reversal will burn up the rectifier, regulator if it has one, and could quite possibly damage the electronic ignition.

 

[Dhadley]

Re: battery hooked up backwards

Good question Bill, but no it's not electronic ignition. It's a form of a magneto ignition. The initial voltage comes from the flywheel magnets and coils on the stator rather than from a battery. It'll actually run without a battery if you rope start it.

 

[byacey]

Re: battery hooked up backwards

Thanks Dhadley, with that in mind I would have to agree with Joe. The problem is likely not related to the battery being reversed. <br /><br />One question I have though, is the alternator stator field using the same magnets as the magneto under the flywheel? If so and the rectifier was shorted, it could possibly sap enough of the magnetic field due to the high current through the stator thus reducing the efficiency of the magnetos.