Recharging magneto, current draw

[Bruce Compton]

I'm planning on recharging the magneto on my '14 and it already has an outside oiler at the mag post. Can I safely recharge the mag through the spring-loaded oiler post or will the current be too high and do damage?

[speedytinc]

The mag post will turn into a heating element, destroying its usefulness. Minimally taking the temper out, but possibly burning out like a light filament. Do not charge thru it.

Do you know to remove the inspection cover to check the alignment of the magnets over the mag poles??
Look for 2 magnet brass screws to be equally distanced from the top center.

[TXGOAT2]

I would not want to apply heavy current at the mag contact button either. Have a solid, secure connection at the mag button, then switch the current on/off elsewhere.

[Moxie26]

Simple set-up to recharge magneto with none of the afore mentioned damage.

[speedytinc]

I would not want to apply heavy current at the mag contact button either. Have a solid, secure connection at the mag button, then switch the current on/off elsewhere.

Mag contact is made & held on the button. A negative lead is "flashed" on the HH
When using a hi amp dc arc welder, we use a valve & clamp on the head. The stem is insulated with a slipped on piece of rubber hose.Firmly held down on the button.

[Distagon2]

The magnet charging process shown in the diagram looks quite simple, except for the question of who the heck has six 6-volt batteries handy to do this procedure. I guess you could ask to borrow some of your buddies batteries and hook them up as shown.

[speedytinc]

Simple set-up to recharge magneto with none of the afore mentioned damage.

AS shown, this method charges thru the mag post. Might be ok with this low voltage, but I wouldnt even risk it here. To get magnet saturation, a higher amp shock is needed. Either a high amp dc arc welder or I use 4 car batteries. (48V)
Also a compass is wonderful, but un necessary. The best alignment comes from a visual sighting of the magnet positions va the brass hold down screws.

See Tom Carnagee's (spelling?)post on in car recharging.

[Moxie26]

Distagon2 & Bruce.... Picture was saved from an old manual. Today we can use three 12 volt batteries, and still do the recharge. Just remember to flash your contact meeting very brief contacts and you will get sparks. Not to worry just stay away from natural gas or liquid gasoline fumes so there's no accident. There will be no destruction of the magneto post internals. Let us know how you make out with the three 12 volt batteries magneto charge.

[Moxie26]

After setting up position of the magneto magnets to the magneto ring and giving them a few zaps, I do turn the flywheel with a helper using the hand crank 1/4 turn, and then I repeat the series of flashes.. and then another quarter turn to set position with another series of flashes. Not all magneto ring and flywheel alignment gaps are equal. Bearing wear will introduce wider gaps at the bottom of the magneto and closer gaps at the top of the magneto, so to equalize or try to equalize magneto strength this is why I zap the magnets every quarter turn to even out total magneto output.

[speedytinc]

Using Tom C's method you will get saturation with 1 sparking. No need to align the old polarity either.
No need to turn the motor 1/4 turns unless some of your mag coils are shorted.

[J1MGOLDEN]

Last month, I had a 1918 engine that the compass needle pointed right to the case or pedal any place where it was moved.

I removed the spark plugs, jacked up a rear wheel to reduce any drag and set the transmission in neutral.

Three quick zaps with my 40 Volt 40 Amp golf cart battery charger coupled only to that post made the Mag work like new.

[speedytinc]

Last month, I had a 1918 engine that the compass needle pointed right to the case or pedal any place where it was moved.

I removed the spark plugs, jacked up a rear wheel to reduce any drag and set the transmission in neutral.

Three quick zaps with my 40 Volt 40 Amp golf cart battery charger coupled only to that post made the Mag work like new.

Like new? Did you check the output with an analog ac meter?
Would like to know the actual output to know if it did the recharge well or just adequate.
You may have found a cheap unit/way to do the job.

[J1MGOLDEN]

That unit cost me $40, but they are not used anymore.

A friend got one for free.

If you measure the resistance and get 1 ohm, then you measure the current and get 40 amps, a little math will tell you there is 40 Volts there.

This is what an original one will look like.

[Kurt in NJ]

when I first started working on my 17 I was worried about starting it, cranking as fast as i could with the head off the best that the magneto produced was 3 volts.
After reading about the on car recharge methods I figured to try it.
Removed the terminal post and took a long carriage bolt, slipped a piece of hose over it to insulate from the hogshead , folded cardboard underneath the coil box the hold the bolt against the contact.
3 heavy 12v batteries in series with heavy cables, my good 00 welding wire jumper cables to connect to the car.
Positioned the flywheel as has been posted looking in through the band cover, and piston position, the piston edge level with the block deck a little after tdc compression #1 also positioned the flywheel properly, put a paint mark on the flywheel too.
Took a bolt and nut and put into the hogshead for a contact, the first tap making contact made a big thunk as it shifted the crankshaft the .025 thousands of end play, gave it about 10-15 pulses.
Now with the magnet gap as it’s greatest clearance it will make peaks of 12 volts spinning the fastest i could, normal hand cranking it makes peaks of 9 volts while lighting the headlights dim.
The car starts easily on magneto, don’t even have to pull the crank hard, just enough to spin it over, I am very happy with the results.
My thoughts were to use the heavy wire, large batteries to allow as many amps as it would take, and heavy wires to allow fast rise of amperage—- it worked for me.