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1989 40hp mercury outboard no spark

pber

New member
"I have a 1989 Mercury 40hp &#

"I have a 1989 Mercury 40hp (4 cyl) outboard that will not start. It does not seem to spark. It ran last fall, this spring it will not run. The only change is a new starting battery.

If I pull a plug and look for spark against the block there is nothing (on all 4 plugs). All 4 plugs have good spark if I test them on the push mower.

The coils seem ok. (short between +/- terminals and between coil tower and either +/- it is open).

The trigger values are 800 ohms between brown and white/black trigger leads as well 800 ohms between White and Violet trigger leads

The stator readings worry me. I have open between Blue and Blue/white and 135ohms between red and red/white. What are the correct readings for the stator? Also is it possible for the stator to just stop working over winter?

Once again, the only change from last fall when it work and this spring is a new starting battery."
 
kill switch on controle box?

kill switch on controle box?
disconect black/yellow wire on powerpack and look for spark
 
I manually tested both the dea

I manually tested both the dead man switch and the mercury tilt switch and they seem ok. I will pull the wire from the switchbox and retest when I get home. I'll post the results.
Thanks.
 
Removed BK/YL wire from switch

Removed BK/YL wire from switchbox and still no spark. Also remove YL/YL wires from rectifier and no spark as well.

Stator readings: BL and BL/WH - open
RD and RD/WH - 135ohms
YL and YL - 1.2ohms

I believe the BL and BL/WH should be between 5k and 7k ohms so I think my stator is done. What would cause the stator to blow.
 
"sorry i dont have the values

"sorry i dont have the values for the stator test but I think you're on the right path, pop the flywheel and take a look. corrosion, old age, mice could be anything"
 
"Unplug the main wiring harnes

"Unplug the main wiring harness at the engine,
trip the starter solenoid and check for spark,
this will isolate the engine from the control
box/ignition switch."
 
Turns out the stator and the s

Turns out the stator and the switchbox were blown. One probably took out the other. She purrs like a kitten now.

Thanks for all the help.
 
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