Magneto suddenly stopped providing current.
 

I was out driving in my 1915 Model T a few weekends ago and it suddenly stopped running. I knew the fuel level was low in the tank; I was going up a hill - so I assumed it was a fuel issue. Yesterday I cleaned the fuel lines etc.

Car started on BATT okay as usual - I thought the problem was solved. But when I went to switch it over to MAG it cut out. Flicked it back to BATT - all was fine. I have removed the coils and dismounted the coil box. Took apart the front switch, cleaned it up and tested the circuitry. Cleaned the connections in the box and at the rear and tested the circuits again.

So I am positive that all is fine back to the Magneto contact assembly. Question - as my next step will be to remove the Magneto Contact assembly and check it out - how do I ascertain that this may be the problem? What do I look for? Do they wear out over time? And then just suddenly fault?

Any thoughts gratefully appreciated.

Re: Magneto suddenly stopped providing current.
 

Might be as simple as an accumulation of crud, band lining lint, etc. - take the 3 screws out whilst holding the contact down as it is spring loaded, remove it & clean it off.

Re: Magneto suddenly stopped providing current.
 

You could remove the wire from the contact and using an analog meter do a quick check for output with the car running on battery.

Re: Magneto suddenly stopped providing current.
 

Well, I removed the three screws, held down the contact, gently removed my hand - and nothing moved! Looked at the unit, cleaned it up and adjusted the length of the spring. Replaced everything and started the car. Flicked it over to MAG and it continued running.

I think that the tip of the spring had just worn away so much that no contact was being made. Interesting the unit looked nothing like those the suppliers currently sell - it was like to one on the top of the picture.

Re: Magneto suddenly stopped providing current.
 

The top contact is an original - the repro apparently has the spring stuck in a compressed position !

Re: Magneto suddenly stopped providing current.
 

Ford brand magneto pick up posts have been replaced with all sorts of different types of aftermarket parts. Some were oil catchers. A person never knows what it will have until the first time they pull it off and have a look. They just have to be able to pick up the energy pulses frome the coil plate. A lot of folks put a gauge on them to see what the output is. If a person has magneto operated headlights then that's another way to check the output.

The ones Lang's sells aren't like OEM ones either but they will work.