Dead Magnets

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Collector Inspector
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Dead Magnets

Post by Collector Inspector »

Interesting this, I have an old MS39 Elto single, in good nick for what it is but no spark , after rebuilding the ignition system etc and checking coil etc etc.

Dead Magnets!

So, no spark!

Now what did I read on SOS about this and spinning a flywheel then maybe it would help before getting carried away.

So, with everything checked out I got my drill and an adapter 9/16th and proceded to "Spin" while having the HT lead in my palm and a finger on the block.

Spin, spin.......is that a tickle I felt? YEP! and the magnet had some attraction to a screwdriver!

I am still spinning and it getting to the stage that I can not hold the HT lead and ground with just one finger. Yeh, my hole hand now and is getting kinda shocking :shock:

OK, still rotating, magnets are getting stronger but still not enough to actually spark an air gap.

This advice is very sound!

I will let you know how it goes just spinning etc, looks and feels the job but!

I am going to get a very strong magnet with north.south defined and check north south on the flywheel and stroke the little sod a lot anyway...........not me necessarily being a stroker by the way.

Yeh, spinning with a drill actually gets things motivated!

Well Done!

B
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pistnbroke
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Re: Dead Magnets

Post by pistnbroke »

rather than stroke you could try this ..

find which poles are N and S inside the flywheel with a small compass ( compass points to south pole of a magnet remember not north as the north pole of the earth is a magnetic south pole )

Say the first mag to approach the magneto coil is a North.

then bring out a wire from the coil primary and then pass a current of about 1 A through the primary such that the first pole of the magneto core is also north . Spin the system with the current flowing for say 15 min and test again ... as the duff magnets pass the magnetised coil core there is a sudden rise in magnetism in the magnets which aligns the structure and builds the magnetic field ..

check current does not heat coil a 10w bulb and a car battery should be ideal ( ausie cars have 10w bulbs )
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Re: Dead Magnets

Post by Collector Inspector »

YES, I remember reading somewhere along those lines! It all confused me as the descriptions were never that clear.

Takes an Australian to say much in few words eh?

Image

I will get the necessary together and continue with that Mate!

As far as my efforts went last night, just spinning, it did not work as by morning the magnet had lost its' even weak attraction.............would have to start again just to get the same saturation and to loose it again. I mean, the magnet was just a lump of iron to start with.

I can check current with my Fluke meter.

Ta for that!

B
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Re: Dead Magnets

Post by Collector Inspector »

I would imagine that the points and condenser would be taken out of circuit for this yeh?

I slipped some new button magnets in to the assembly, just to see what would happen.

Great belt on the hand but still not enough to actually spark the plug so spin in a field it is lets see what happens.

B
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pistnbroke
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Re: Dead Magnets

Post by pistnbroke »

yes disconnect the contacts ..the magnetic field you create should snap through the old magnets and re viaalise them ...you must bare in mind why did they loose the magnetism ? vibration ? heat ?
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Re: Dead Magnets

Post by Collector Inspector »

Loss of magnetics..............gd question wish I could tell 100%

the motor is 71 years old not used for at least say 60 years.

the magnets are just lumps of sand cast iron, nothing flash

Image

Vibration not known until I get it to run and as far as a knock I can see no evidence apart from some slight scuff marks as though the flywheel came loose maybe?

It has a new spark plug (Way long ago) which works mint when tested on any other motor I have. Pic attached so maybe someone can date it? Olympic L10 Aluminium.

Image

It is missing the plug cover/cowl which means someone had a problem, lost interest and now cowls are FN hard to get of course. Bit like the same for an Anzani Minor.

All very interesting playing but................
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