Flywheel magnets recharge

[Michael Anfossi]

Hello,
Who in the club can recharge a 1936 Evinrude model 4148 flywheel?
Thanks

[Tubs]

I can recharge flywheel magnets but while this does increase
the magnetism it doesn’t benefit how one starts or runs. Most
motors from this time have never been recharged and they start
and run just fine so don’t give up on this motor because you
feel its necessary to get it going. After making a considerable
investment in a magnet charger I stopped recharging magnets
of the motors I have restored as there was no obvious benefit
from doing so. I just recently got this 1937 Johnson running
again. Although I have only been able to bench test it, it seems to
be ready to be put back in use and that is the plan this summer.
I’d be more than willing to do yours but the cost of shipping
(both ways) doesn’t justify the result IMO.

https://www.youtube.com/watch?v=S_cTrjdTmzs&t=3s

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

• This reply was modified 4 years, 9 months ago by Tubs.

[Mumbles]

Michael Anfossi wrote:

Hello,
Who in the club can recharge a 1936 Evinrude model 4148 flywheel?
Thanks

Do you have a local chapter near you as some members own a Stevens or similar unit needed to charge weak magnets. A strong magnetic field is necessary to generate a good spark and iron flywheel magnets in pre war motors tend to degenerate with age but not so much for post war magnets made out of ALNICO.

Since I couldn’t find a charger anywhere, I ended up making one.

[geary]

Michael,
Our Western Reserve Chapter has a gentleman ( Bill Mohat) who has a magnet re-charger. Bill will recharge your flywheel for free if you send it to him and pay for the shipping back ! You can contact Bill at ( wmohat@gmail.com ) or call him, his no. is in the directory.

Gary

[bob-d]

Tubs, the idle on your motor is amazing. So smooth. Job well done.
Spectacular restoration as usual.
Bob D

[Michael Anfossi]

Rubs,
I hear you and will try to make sure everything else is good. I do have spark on plugs outside of cylinders, but not sure it is strong enough. Magnets feel kinda weak to me so hence the question. Engine in question is a 1036 Evinrude fisherman, model 4148.
Mumbles, unfortunately there is no chapter near me and I am the only member in the country – Bermuda. Nice looking charger BTW.

[Tubs]

The little 1/2 hp. motors from the late 30’s
have the smallest flywheel and likewise
the smallest magnets of any outboard motor.
As they are pre war motors they have iron
magnets and they do loose magnesium over
time. They also have a coil that has failed
by now. In this video the motor is running
using a coil from a 1949 Mercury 10 hp.
KF-7 Super 10. That magneto has permanent
magnets that are not only larger but way
stronger than what is in the 1/2 hp. flywheel.
In spite of the fact that there is a major
reduction in magnesium there is still enough
to produce a spark so the motor will start and
run. Its a myth that these early magnetos need
to be recharged to start and run properly. The
problem with spreading this myth is convincing
people they have a problem and they are not
able to solve it when in fact that is not their
problem at all. You would be that example. The
strongest spark is produced when the polarity
from the magnets changes as it passes over the
coil. This is when the points should open. You
achieve this by setting the points at the proper gap.

https://www.youtube.com/watch?v=71W9cPMV09A

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

[JOHN HOLBIK]

Well said Mr Tubs.

[Mumbles]

There’s some interesting observations by club member Bill Mohat in this older thread about recharging flywheel magnets. In particular, how the sizes and composition of the magnets changed thru the years affecting their strength and their need for periodic recharging. Obviously, not all magnetos are the same so test results for one will not necessarily apply to all.

https://www.aomci.org/forums/topic/recharge-magnets-on-fly-wheel/

[Tubs]

Mr. Mohat submitted an article to the outboarder after doing considerable testing. While he was able to get magnetos to produce spark at a lower rpm after charging, it was below what a motor would run. He made no claim that any of the motors tested started easier and only speculated that recharging the magnets would improve the idle. Quote – “However, on other outboards with similar magnet structures, an improvement in magnetic field strength, you -“might”- see a dramatic improvement in the low -RPM idle speed” as there wasn’t any evidence of that in the examples he tested as I read the article. My interest in outboard motors is largely in pre WW-IImotors starting in 1945 with a 1937 Pal. A considerable amount of motors have come my way over the years and week magnets have never been and issue in getting a motor to run. I was able to purchase a magnet recharge in the 90″s. I was sure I would now be able to start my smaller motors with just a flick of my wrist. It quickly became evident that increasing the magnetism wasn’t having any effect on how my motors would start or run. I have no idea why anyone feels the need to promote this myth but I can find no evidence that its true so I will continue to dispute it for the reason I stated above. If you go to 4:53 in the video in the link you posted you’ll see that the conclusion after recharging is — “the spark is about the same”. But it doesn’t matter even if there was an improvement. Its of no value unless you have access to a charger. Letting a motor sit because don’t have access to one or the expense of shipping are poor options compared to just using it.

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

[Author]

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