Trouble with Mercury 850 series

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

newme7 - 07 Jul 2008 10:22 GMT

I’m having trouble with a mercury 850 series outboard motor, 85hp,
early 80’s. I’ve replaced a lot of the wires due to corrusion, but I
can’t get power from the battery to the starter to turn over. The
battery is fine, checked it, replaced selenoid, didn’t work. I can get
it to turn over by hardwiring it straight from battery to starter, so
starter is fine.
Any idea’s would be greatly appretiated, thanks!

Signature

Posted at author's request, using moderated http://www.BoatingForumz.com interface
Thread archive: http://www.BoatingForumz.com/Trouble-Mercury-850-series-ftopict99656.html

Reply to this Message

Larry - 07 Jul 2008 15:02 GMT

newme7 <none@000.com> wrote in news:381213_4974281a8bfbf340429bf9aac6451a53
@boatingforumz.com:

> Any idea's would be greatly appretiated, thanks!

Rotten wire in there somewhere, probably hidden inside a the insulation.
That's all there is between the battery and the starter solenoid.

What voltage is on the battery wire at the solenoid and what happens to
that voltage when you click the solenoid? If the voltage drops hard, bad
wiring. If it remains high, bad starter. If it drops and the wires get
hot...shorted starter.... pretty simple circuit.

Also....measure the voltage between the NEGATIVE post on the battery and
the BLOCK on the motor. It's great fun to walk casually up to someone
who's been pouring over a problem like this for hours on the + side of the
battery, then point out the negative side isn't connected to the block....
(c;

From the block to the negative battery post should always read zero...even
with the starter pulling hard.

Reply to this Message

Boat Forum / Electronics / July 2008

Trouble with Mercury 850 series