Engine died down at high RPM.

You check for voltage to ground from the stator first, if any is found then the stator is bad. Then you check the peak voltage coming out of the charge coils(stator), 150 is minumum for your app at cranking speed to the packs(with packs disconnected). Then you'll need a PL-88 to install in place of the coils, and you should have 130 volts minumum there. If you have 150 going in, but less than 130 coming out you'll most likely need a new pack. The next test is for the trigger coil, they should produce 0.4V at cranking speed. Obviously this is much easier with a book in front of you outlining which connectors to check. If you can't find a true PRV meter for testing magnetos, then your best bet is to swap the packs from side to side. It shouldn't take but 10-15 minutes to swap them, and if the problem follows the pack then replace that pack. You can also buy a CDI 511-9773 and use a standard DVOM(digital, not analog). The OMC tool isn't expensive, but it's tough to come by. The CDI adapter lists for $90, but can normally be found for $45 online(unless you need it ASAP, like I did).
 
Mushman:

Before you do anything, I recommend you change all of the spark plug wires. I had the exact same problem and symptoms with a 1989 Evinrude 200.

Powerpack, coils, etc., were suspected (and changed), but the answer turned out to be much simpler and cheaper. My wires looked fine, but several had developed invisible cracks in the insulation which allowed them to arc (ground out the cylinders to which they were attached) at high speeds. Consequently, RPMs went down, and the spark plugs on those cylinders always appeared wet. At idle and low speeds all cylinders had spark, and everything looked fine.

A quick test that will generally confirm an ignition wire problem is to spray all of the wires with silicone, then take a run. The silicone is usually enough to fill any insulation cracks for a short while, so if the engine runs fine, you know it's the wires.

I hope that's your only problem. Under any circumstances, changing the wires every few years is good preventive maintenance.
 
I didn't get to the boat today, go figure the wife wanted to spend time with her and the kids today, but tomorrow I'll check what I can if its not pouring.
I was looking at the diagrams and I can see how the plugs on each side are related to the each of the two packs.
Would a bad pack bog me down at high rpms?, or can the pack only show signs of failing at high rpms?.
Should I open her up and see if it does it again, or just let it run for a while and take a look at the plugs?.
I think I'll try swapping the packs to see if the plugs on the other side get all fouled up.
I'll get back with results as soon as I get to the boat.
 
Bad packs can do all sorts of wacky problems. They can cause them to mis-fire, not fire, and other sorts of hair pulling problems. They are the 1 item that a JOHNNY-RUDE owner should carry for a spare.
 
Had the same problem today down in Ocean City. On the way back my 96 Johnson 112 would be running 5000 rpm then it would drop to 3500 or so for as little as a second and as much as 10 seconds. Had this problem at the end of the year last year and changed hose and ball also installed new 10 micron racor filter/seperator. Its funny ran for two days fine and then it started acting up. Left tank was near empty so I switched it to the right tank which was full. Sill did it. Its driving me nuts.
 
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Bad packs can do all sorts of wacky problems. They can cause them to mis-fire, not fire, and other sorts of hair pulling problems. They are the 1 item that a JOHNNY-RUDE owner should carry for a spare.
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I agree!! when mine was bad I went from thinking bad gas, bad plugs, bad coils, bad ball on the fuel line, ect... ect... ect... then I saw a pack on ebay for cheap, I ordered it and all was perfect in the world!!
 
We had some nasty weather here today so I didn't get to anything, but I did pass by a marine store today and picked up a new set of plug wires, which I was planning to replace since last year.
The wires he gave me were gray and have Ht on them, the originals were black and say copper core on them.
According to the johnson site they list a different part# than the ones I got.
Will the ones I picked up be o.k., or should I return them and look for the specific part#?.
 
I finally got to take the boat out for a good run today after a pretty bad week weather wise, and it looks as if it was either bad fuel, or the wires.
I looked at the old wires with my ohm meter and one of them was so corroded it wouldnt show me a short from one end to the other.
I still have to take a look at the plugs to see how they look, but the weather turned sour again so I'll give it a try later on this week.
The fishing has been getting good around here so I'm glad I'm back up and running.
Thanks to all for the help, I'll look further into the suggestions if the problem shows up again.
 
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