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Johnson 30hp ignition question

R

Rimmert

New member
Hello

I have a 1990 johnson 30hp outboard which has troubled me for a few days. A few weeks ago I turned the flywheel by hand and noticed that de movable plate with the ignition moved as the flywheel passed by it. A few days ago i took the flywheel of en there was some evidence of something touching so I adjusted it and it seems to be better now. However when i disconnect the ignition from the throttle lever and turn it to full advance. (fully anti clockwise when viewed from above) it rest againtst the stop. But every time the flywheel passed it moved back about half an inch from the stop and then stayed there when the flywheel passed again. I have been stuck with this for days. But today I thought I knew the answer. It only moves with the layerd coil, Not the powerpack, When i removed the coil it didnt move so i though it must be touching the coil. But is it possible that the ignition plate is pulled back because of the magnetic field that is generated when the flywheel moves along the coil? If this is the case than there wouldnt be a problem right? Because in normal operation the thottle arm keeps the plate where it should be. and it wouldnt be touching anything anymore if it is just a magnetic effect?

And does it matter how close the coils and powerpack are to the flywheel? or doesn't it matter with electronic ignition? Because i have been told that with electronic ignition on an outboard as long as you have a spark it's fine, unlike the old points system where everything has to be checked with feeler gauges etc.

Any insight/help would be appreciated.
Kind regards Rimmert
 
The following pertains to all coils attached to the armature plate.

(Magneto & Driver Coil Alignment)
(J. Reeves)

To align the coils properly, have the metal vertical portion of the coil yokes aligned with the inside edge of the bevel that exists on the top portion of the aluminum seat upon which the coils sit. This creates the proper distance between the coils and the flywheel magnets. Faulty alignment creates friction and the yokes of the coils heat up, turn blue and expand.
 
thanks for your reply, I thought that this was the case and I have already aligned them flush to the seat. About the movement of the ignition plate, Is this correct that it could be caused by the flywheel magnets pulling the plate around? Because I'm a bit paranoid about things touching the flywheel.
 
I'm saying to align with the inside top bevel edge..... you're saying that you're aligning them flush.

If that means you're aligning them with the straight vertical portion of the aluminum coil seat... then yes, they're too close to and could touch the magnets.
 
Hello

I've still been at it with the ignition. I had the engine back together tonight but no spark. I Have a feeling it is the charging coil under the flywheel. I saw it has been damaged at the top, because i could see windings through the casing on the top. I don't know for sure if any of the wires from the coil have been cut or damaged but they could very well be. Also I dropped it overboard inadvertently but i got it back within 15 minutes, But i guess it's not the best thing to do. And on another note if the windings are clipped does it matter? I think so but i could understand why, because the coil is copper wire without insulation right? so I thought if it all makes contact 1 or 2 broken wire in the coil should't matter. But if someone could confirm it that would help allot.

I would like to understand the system a bit better before i order a new coil if it's not neccecary, I live in the Netherlands and the shipping is as much as the coil, but if it's probably broken i'll get a new one.

The part that I mean under the flywheel (just in case)
http://www.marineengine.com/parts/images/hg/omc/0584333.jpg
 
No , no it is not just copper wire.------------It is " magnet wire " and it has a thin coat of insulation on it.----------Wires must not touch winding to winding.
 
Right..... Then that would probably explain the lack of a spark. One broken wire in the winding would be enough to render it useless then? Because I saw the wiring thourgh the damadeg casing. And it sparked before just fine. So I probably damaged them. Even if they are not touching each other a break would cut out the "circuit"? And when connecting a new coil under the flywheel to the powerpack. Are the two plugs a positive and a negative? or can it just be plugged in regardless?

Regards Rimmert
 
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