Battery or charging electrical issue - 35 HP Mercury Outboard - 1988

R

rstier

Petty Officer 3rd Class
Joined
Jul 19, 2005
Messages
90
Hi,
Could someone point me in the right direction. I have a 1988 Mercury 35 HP Outboard. The battery was new last season and I kept it on a battery tender all winter. I launched this weekend and the battery keeps running dead. I am wondering if it is a charging issue (rectifier or other)? I tried disconnecting both battery connections and the outboard continues to run which I assume is a good sign. While they were disconnected and the motor was running, I did a voltage check between the positive and negative terminals. I get no DC reading. What next?
Thanks!
Ron
 
A

aussieflash

Lieutenant Junior Grade
Joined
Feb 5, 2011
Messages
1,004
Re: Battery or charging electrical issue - 35 HP Mercury Outboard - 1988

Never Ever disconnect battery while outboard running.Will damage ignition and various electricals.This should never be done with any engine.
 
R

rstier

Petty Officer 3rd Class
Joined
Jul 19, 2005
Messages
90
Re: Battery or charging electrical issue - 35 HP Mercury Outboard - 1988

Ok, that was a bad move. Any comments on troubleshooting this further?
Thanks,
Ron

aussieflash said:
Never Ever disconnect battery while outboard running.Will damage ignition and various electricals.This should never be done with any engine.
Click to expand...
 
L

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Battery or charging electrical issue - 35 HP Mercury Outboard - 1988

The quickest way to check output is hook a volt meter across the battery terminals start the engine and see if you gain voltage. otherwise check for contiuity between the 3 yellow wires at the rectifier (disconnected from the rrctifier) and here's the rectifier test.
scan-4.jpg
 
R

rstier

Petty Officer 3rd Class
Joined
Jul 19, 2005
Messages
90
Re: Battery or charging electrical issue - 35 HP Mercury Outboard - 1988

Perfect, thanks. At least the rectifier is easy to get at on this one.


Laddies said:
The quickest way to check output is hook a volt meter across the battery terminals start the engine and see if you gain voltage. otherwise check for contiuity between the 3 yellow wires at the rectifier (disconnected from the rrctifier) and here's the rectifier test.
scan-4.jpg
Click to expand...
 
You must log in or register to reply here.
Top