B & S Flywheel Magnets

Gunnar Storsveen

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Briggs & Stratton Flywheel magnets:
Are there one or tree magnets and which POLE orientation?
See appended 2 files
 

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  • B and S_Flywheel Magnets.jpg
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We need a picture of the flywheel for reference. There are different designs.

What engine number is the flywheel on?

If it is only for triggering the coil, I don't think pole direction is important. If it is the magnets attached to the underside inner portion of the flywheel then the poles have to alternate between N. & S. polarity.
 

Rivets

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Type this into your search engine and I’ll bet you’ll find the answer to all your questions. how do briggs ignition systems work diagram
 

Gunnar Storsveen

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We need a picture of the flywheel for reference. There are different designs.

What engine number is the flywheel on?

If it is only for triggering the coil, I don't think pole direction is important. If it is the magnets attached to the underside inner portion of the flywheel then the poles have to alternate between N. & S. polarity.
I’ll find the engine number after the first weekend and may be open the engine. I am interrested in the MAGNETRON ignition system with two Darlington transistors. This ignition system made the B & S engines more reliable.
This summer I made a barn found:
42 years B & S Magnetron engine with generator: It fired after using the recoil som times.
👏👌😀
 

StarTech

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We need a picture of the flywheel for reference. There are different designs.

What engine number is the flywheel on?

If it is only for triggering the coil, I don't think pole direction is important. If it is the magnets attached to the underside inner portion of the flywheel then the poles have to alternate between N. & S. polarity.
Yes the polarity is important. That why some old point systems [cast iron blocks] will not work when converted; until, the magnets are re-polarized; otherwords, the North/South flipped. This because the cast iron point system used a positive ground vs the current negative ground system.

Opps showing my age...
 

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Hi StarTech,

I had forgot the differences between coils because I rarely get anything with points anymore. Points ignition systems were just being phased out back when I was starting out many years ago.

I had also certainly forgot about the flywheel magnet polarity and correct coil mounting orientation.

Here is a video that I found online:
 
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