Page 1 of 1

Magneto marks question

Posted: Sat May 02, 2020 3:48 pm
by westeagle
I started from scratch today to reset the timing and always wondered what the round punch marks beside the opposing factory slash marks meant? (see photo). Would they have been put there by the factory, or by a service shop as a reference?

Guess they're factory....I

Posted: Sat May 02, 2020 4:04 pm
by schrader7032
Guess they're factory....I had them on mine but I didn't even notice until now...I didn't even consider them in the alignment.

True North?

Posted: Sat May 02, 2020 5:52 pm
by westeagle
Could the punch marks be the true north/south parts of the magnet as measured after manufacturing?

I wouldn't over think it. I

Posted: Sat May 02, 2020 6:06 pm
by schrader7032
I wouldn't over think it. I checked the Rinckes book and it just mentions to put the long slit into the viewing port on the magneto body. There are two slits and I don't think it makes any difference. The magneto works by cutting the magnetic field which produces current in the coil resulting a spark.

As a bit of analogy, the points system with a condenser (a battery-coil ignition) has two lobes on it. The magneto has two slits in it. The camshaft rotates at 1/2 speed relative to the crankshaft. So when the flywheel rotates 360 degrees after firing one cylinder (on compression stroke), then the second cylinder will be on the compression stroke. The magneto must rotate 180 degrees so the other slit (representing the other pole of the magneto) crosses and creates current in the coil to fire.

I never questioned any other marks on my permanent magnet...I just aligned the slit.