85 Mercury 35hp Charging Problem?

mee7070

Recruit
Joined
Jul 5, 2005
Messages
1
Not sure if this is a real problem. The motor is electric start. Should this motor have a charging system? Motor runs fine. However, while viewing my Fish Finder in self-test mode other day, noticed my voltage was 12.7 volts. Shut the motor off, still 12.7 volts. Started the motor again, notice a slight dip then back to 12.7 volts. Rev'd the motor up, still 12.7 volts. And finally, while the motor was running, disconnected the main (+) line on the Battery, still 12.7 volts. When I connected my battery charger, voltage went to 13.1 volts. Guess I've never paid attention before because I've always kept the battery on a charger when not in use.
 

WillyBWright

Fleet Admiral
Joined
Dec 29, 2003
Messages
8,200
Re: 85 Mercury 35hp Charging Problem?

Welcome to iboats. :) <br /><br />Look for a little black square doodad with 2 yellow and one red wire atached. It's probably bad. They fail from loose, corroded, or reversed battery connections. In the $35 ballpark.
 

vampirefish

Petty Officer 2nd Class
Joined
Feb 14, 2005
Messages
195
Re: 85 Mercury 35hp Charging Problem?

Hello, I seem to have the same problem...in fact I replaced my rectifier and still don't see a jump in the voltage with the engine running. Any suggestions?
 

Laotzu

Petty Officer 2nd Class
Joined
Aug 1, 2004
Messages
150
Re: 85 Mercury 35hp Charging Problem?

Vamp, any chance what blew the old rec. also blew the new one? Happened to me once and it was a burnt/shorted regulator.<br /><br />Jerry
 

vampirefish

Petty Officer 2nd Class
Joined
Feb 14, 2005
Messages
195
Re: 85 Mercury 35hp Charging Problem?

I'm not sure if I blew the new one. My stepfather gave the boat to me and said that it never charged the battery when he had it. Since it's a 1966 Merc 95hp o/b, I've learned that there is just a rectifier and stator (as a charging system). I have verified a continuity test from the positive cable that goes to the rectifier, to my battery..however, maybe I killed it this way?... How would I test the green wires to the rectifer (apparently these go to the stator but I'm not sure where they start... the starter?
 
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