60hp electrical problem 1993

headdamage

Cadet
Joined
Sep 11, 2011
Messages
11
The motor is a 1993 Johnson 60hp 3 cylinder longshaft with power trim and tilt.

I have an intermittent electrical problem:

While under power the warning horn will start to make a bit of noise (not the full warning noise), this noise is not loud and varies with motor speed and if I try to adjust the trim.
When this noise is present the power trim and tilt do not work either from the remote control or the switch on the side of the motor.
If I turn the motor off at this point it will not restart, the starter will not turn (have not tried pull starting during this condition).
Note that the motor will stay running ok other than power trim and tilt do not work when this is happening.
Voltage at the battery cable lug on the starter reads approx. 7 volts with ignition on when this problem is taking place (12 volts when things are normal), reads 12v with problem but with ignition turned off.
I can usually get it restarted by moving wires on the Port side of the motor around but this is very random and can take one touch or 30min of messing with it to get it to work.

I've tried unplugging all the plugs and looking for anything loose and I can't figure out where the problem is, I can't even figure out what circuit is at fault.

My best guess is some sort of grounding problem.

Has anyone had this happen and can tell me what to look at? Is there an online wiring diagram for this motor? I haven’t found one.

Thanks for any help.
 

WernerF

Petty Officer 1st Class
Joined
Sep 5, 2011
Messages
320
Voltage at the battery cable lug on the starter reads approx. 7 volts with ignition on when this problem is taking place (12 volts when things are normal), reads 12v with problem but with ignition turned off.

Sounds like you have a bad battery connection. You didn't say where your meter ground was connected to (battery minus or engine ground). Measure directly on the battery lead posts, then on the clamps and then on the engine side in order to find which connection is bad.

Fix it soon as an open battery connection may damage your rectifier/regulator.
 

headdamage

Cadet
Joined
Sep 11, 2011
Messages
11
Looks like I've found the problem. The stud that the main negative battery lead attaches to was loose in the block.
 
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