flywheel magnets

[SCO]

I'm trying to get my '58 Johnson 18 running, will start this weekend, and want to understand the flywheel magnets. Do they get weak over time and use and can you revive them by sticking a properly oriented strong magnet on them for a few days? I would think that weak magnets would cause poor idle spark. This question also applies to my 73 Johnson 135 v4 which runs well but sounds like a 60's muscle car that is setup for WOT and idles rough.

 

[Lark40]

Re: flywheel magnets

The flywheel magnets can weaken, but that's usually due to improper storage of the flywheel when detached from the engine.<br /><br />The only device I've seen for re-magnetizing is an old Stevens machine especially made for this purpose. We had an Evinrude dealership in 1958, and this was required shop equipment. Possibly someone on the AOMCI site could advise you of a home-made method.<br /><br />Simple test: remove flywheel and hold a medium screwdriver against the magnets - does it stick? If so, no problem.

 

[petryshyn]

Re: flywheel magnets

SCO<br />Before you attempt this, be sure you actually have a problem. In most cases, since flywheels have multiple poles, its simpler just to replace with used components.<br />>Remagnetizing can be quite the challenge. The magnetizers that I've used were large and expensive. To remagnetize, it takes a much stronger magnet than the one that failed. The best situation would be to use an electromagnet that operates on a/c (diode in series) This would give a hammering effect needed for deep remagnetizing. I often thought of using an armature growler with a diode in series. <br />>If you do decide to try and revive weakened magnets by the use of stronger permanent magnets attached, tap on the weak ones with a plastic or wood object to jar the material.(don't smash it, just tap it several times)This will speed up the process. <br /><br />good luck....

 

[clanton]

Re: flywheel magnets

On the 1973 V4 135 Johnson too much air gap on timing sensor (trigger) would cause no start, hard starting, misfiring at idle.