Classic cars forum & vehicle restoration.

[Rdover]

Those following my Alldays rolling restoration thread will know that I am the proud owner of a knackered magneto. My question is how do they work (apart from the magnetic induction bit - I have a physics degree albeit 16 out of date) and can I test it by spinning it by hand (I did and no visible spark)?
_________________
Richard

[peter scott]

I'm not sure I can give you a description of their working and I don't doubt there are other faults like shorted turns but isn't the ususal problem with magnetos that the magnet needs re-magnetised?

Pete
_________________
https://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon

[ukdave2002]

I have looked a few, first thing to check is that the fault is not something like a plug, plug wire or other external component

If the magnet has been removed without a keeper it may need "re-charging" magneto's magnet are permanently charged when new, but they do degrade with time, to recharge you effectivly make it the core of an electromagnet (back to your physics!!)

Insulation can break down by either heat or vibration damage, you can rewind coils with better modern insulation.

Got any pic's?

Cheers Dave

[Rdover]

No pics, it's off to the restorers to be rebuilt and a reconditioned one made to match so I have a spare.

Bosch is the best make apparently so I'm lucky there.
_________________
Richard