Merc 850 s/n 4372185

[MLStrickland]

I purchased a Merc 850 and as soon as the battery is connected with or without a switch connected the engine draws 10 amps of current. Any ideas?

 

[Laddies]

Re: Merc 850 s/n 4372185

The rectifier is bad.

 

[Moody Blue]

Re: Merc 850 s/n 4372185

Laddies, you never cease to amaze me with these bits of information. I'll file this info away for future reference.

 

[MLStrickland]

Re: Merc 850 s/n 4372185

Thanks, makes sense. I'll trace it out and pull the rectifier and check it out using my Seloc manual. I'll let you know what I find if you desire.

 

[Chris1956]

Re: Merc 850 s/n 4372185

Marvin, Laddies is likely correct, however on those old motors, the insulation falls off and this can allow the short as well. Check the red wire that runs from the wiring harness to the rectifier for missing insulation. Also check the battery cable that runs from the wiring harness to the starter solenoid.