1987 50hp Evinrude Ignition Problems

[deerhunt799]

First time poster here.

I had a problem last weekend with my motor. Turned out to be a bad coil. I changed the bad coil and it ran great for about 30 minutes. While the motor was at about full throttle, it cut out. It would only hold a rough idle after that. After messing with it for a few, I found out that it would idle and run fine by disconnecting one of the coil wires. Long story short, it would run on each coil independently (one cylinder), but the second I connected the second coil wire, it would start running rough again. So, I know each coil is functioning.

I'm guessing it could be one (or more) of three things. The power pack, stater (sp?), or the trigger. Does anyone have any suggestions on how I could test this so I don't buy anything that isn't necessary?

Thanks in advance for all your help.

 

[angus63]

Re: 1987 50hp Evinrude Ignition Problems

Since both coils work but not together, I would lean towards flywheel magnets or trigger. Stator and powerpack are doing there jobs getting power to the coils, just not at the right time, it seems to me.
Good luck

 

[tashasdaddy]

Re: 1987 50hp Evinrude Ignition Problems

here's several pages of reading and testing. "http://www.boatpartstore.com/page28.asp"

 

[deerhunt799]

Re: 1987 50hp Evinrude Ignition Problems

Thanks for the advise! I will let ya know how it works out later today.

 

[Joe Reeves]

Re: 1987 50hp Evinrude Ignition Problems

I've looked at this thread a few times. Here's my thoughts on it. Perhaps wrong but............

There are two (2) inner flywheel magnets, one being a south pole, the other a north pole.

The timing sensor (trigger) simply takes its clue from whichever pole is passing by the sensor at the time. Bottom line here is that the sensor simply sends a 1.5v signal to whichever SCR within the powerpack is related to either the north or south pole inner flywheel magnet..... meaning the sensor (trigger) is okay.

This leaves the problem area, if both coils are firing at once or are erratic, to be either the flywheel magnets or the SCR switches within the powerpack.

Take a close look at the inner flywheel magnets. Many of them are held in place via some kind of epoxy. That material has been known to melt somewhat which allows the magnets to change their critical position which in turn causes the engine to run erratic..... or not at all. If this condition has taken place, it should be easy to determine, quite obvious.

You can check the magnets to see which is south or north by holding a compass near the slots, BUT not too near as that would magnetize the compass for some time...... the compass if magnetized wears off in time.

If the flywheel inner magnets are indeed where they belong and nothing seems to be amiss in that area..... nothing torn up, no metal filings, etc, and all of the related wiring is frayed, shorted, or missrouted, I'd strongly suspect the powerpack.

When time permits, visit my store (copy/paste) at: stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc