Late jumping in here... I've read all the posts/replies, BUT may have overlooked something (it happens).
1 - The questions asked by GA Boater..... "Were the motors starting and running OK before this??" I didn't see a definite answer to his question... SO... Have those engines every ran since you've owned them?
2 - The ignition on those engines are "Self Contained" meaning that the stator under the flywheel generates approximately 300 AC volts to be applied to the powerpack's capacitor to engine the ignition/spark. The electric starter must crank the engine over at least 300 rpm in order for the stator to generate that proper AC voltage. A slow cranking engine will emit weak, erratic, or no ignition/spark.
3 - If for any reason, battery voltage is applied to the black/yellow wires (kill circuit) of the powerpack.... that alone will destroy the powerpack(s)
4 - The 1989 225hp models incorporate a RED electrical connecting plug assembly... both the female and male portion of the plug must be RED. All spark plugs must be removed to tests the spark. The spark should jump a 7/16" gap with a strong blue lightning like flame... a real SNAP! Does it?
5a - There is a possibility that a short exists in the large RED electrical plug shorting out the black/yellow kill wire. Find that wire and trace it to the powerpack connector and disconnect it (yes, I know you've already performed various checks... humor me).
5b - Also disconnect the large RED electrical plug at the engine. This eliminates any possible existing problems from that RED plug forward... controls, ignition switch, other switches and accessories, etc. You now have 12v existing only to the starter solenoid UNLESS someone has "Mickey Moused" something into the engines wiring harness.
5c - Rig a spark tester with its air gap set to 7/16". Spark testers can be found at any automotive parts store... or you could easily build the following one. Crank the engine via a small jumper from the large battery terminal of the starter solenoid to the small 3/8" nut of the solenoid that engages it. As it stands, the black/yellow wire (kill circuit) is disconnected, the engine cranking over is powering the stator to engage the powerpack to fire the coils.
6 - The stator has two large black coils at the extreme rear of the stator. These are the two coils that generate the AC voltage to the powerpack. That 30amp stator generates much heat, so much that eventually it melts down one or both of those two black coils... and this results in weak or no ignition. Visually examine them both carefully. Should they me dripping a sticky looking substance down on the powerhead area, replace the stator regardless of whatever test reading you may obtain.
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(Spark Tester - Home Made)
(J. Reeves)
You can use a medium size philips screwdriver (#2 I believe) inserted into the spark plug boot spring connector, then hold the screwdriver shank approximately 7/16" away from the block to check the spark or build the following:
A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.
Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:
..........X1..........X2
.................X..(grd)
..........X3..........X4
Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:
http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
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