1976 115 Merc not charging

[jetset9c1]

Hi all,

I've been searching on this, but so far it escapes me.

My motor runs fine, idles fine and in general has no issues. But;

It doesn't charge. I get 12.5 volts when it's off, less then 8 when running, and it doesn't even read at the motor (-1v). My fish finder doesn't work either when the motor is running so to me it seems like something is generating interference while drawing excessive current form the motor.

I've tested the stator (23vAC at idle), and even disconnected it, and the 12v+ line from the rectifier. Same results.


Any thoughts??

 

[jetset9c1]

Re: 1976 115 Merc not charging

Got it.. It was the rectifier. I'm still not sure about the interference with the fish finder.

 

[daveswaves]

Re: 1976 115 Merc not charging

Got it.. It was the rectifier. I'm still not sure about the interference with the fish finder.

It was not really interference, the shorted rectifier was pulling the voltage down to 8 which is too low for the fishfinder to work properly.

 

[arsenalpsu]

Re: 1976 115 Merc not charging

this is what i used, works great... http://www.allelectronics.com/make-a-store/item/FWB-352/35-A-200-PIV-BRIDGE-RECTIFIER//1.html

It's rated higher than the standard replacement and for a little extra work it can save you $$