Evinrude SportFour Ignition Questions

[Mumbles]

The Boat House wrote:

Electronic ignition coils have a module built into them so they don’t need points to fire them, only the flywheels magnetic field passing by them. This works on the same principle as the Atom or Nova II ignition modules do. Points and condensers can be removed with the module now firing the coil.

[The Boat House]

https://youtu.be/bpT9MRgZa58

[hank1995]

Nice job on the little video. Thanks. I like the idea of the ignition modules – I have a hard time picturing the spindly original points opening and closing consistently at 4K RPM – but of course they did and do. What about placement of the modules? The points open when the inner arm is contacted by the lobe or cam. The magnet in the flywheel has gone by or is going by (?) creating a magnetic field (inducing) in the primary windings – then collapses when the points open. On an OMC or Mercury ignition from the 50’s, the mag plate is rotated to retard and advance the spark and control the throttle. But it’s not timed to a specific point – say a few degrees BTDC like on older car. Presumably full advance is somewhere in the 30 BTDC range and full retard is 2-3 BTDC but that’s all been engineered/manufactured in. Just thinking this thru.

[george-emmanuel]

I still don’t understand why people want to modify a magneto when there are plenty of good, spare parts out there. Rarely have I seen points in motors that need to be replaced. I think what happens is people pop the flywheel and see a mess under the flywheel and assume everything needs to be replaced. Remember, these motors ran well and were dependable with the original parts.

Take a moment and do some research. Make sure what you have is no longer fixable before you start doing modifications. Coils used on the SportFour were common to other motors. Condensors are easily obtainable. Point usually clean up well. I see too many people panic when confronted with a restoration they have little knowledge on. Do your research. Ask questions. Evaluate answers. Seek help.

I have a 1935 SportFour that had a slightly bent rod. Motor ran fine but had a slight knock. I found a replacement rod and installed it. I did the basics on the mag. I went through the carb and that engine runs great! I towed another boat at idle for an hour and a half and the motor never missed a beat.

george

[hank1995]

Tubs – The one coil as in the pic has been broken at the tab – you can see the little glint. I get nothing at any setting. The other intact coil shows 6.80 at the 20K setting and the primary starts at 1.2 and quickly drops to .5. And am I on the right track with placement of the modules?

[The Boat House]

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• This reply was modified 3 years, 2 months ago by The Boat House.

[hank1995]

?

[The Boat House]

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• This reply was modified 3 years, 2 months ago by The Boat House.

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