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Jim, I don’t believe my the Model M was offered without a magneto,
but there were certainly some models during some years that had the
Evinrude style timer below the flywheel.
Craib’s website shows some for 1913, and I have an ad for 1915 showing
a timer set-up.
One ad said all 1914 models equipped with a high tension reversible magneto.
That said, I’m not exactly sure what year mine is.
The upper crankcase does not looked machined for a timer, but
there may be room to rig one up.
One motor on Craib’s site appears to have been converted from magneto,
to some sort of timer affair running off the magneto drive shaft.
http://www.cailleoutboards.com/rowboat/ … -002f.html
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Jim, Yes on the lathe. Don’t have any photos of the bottom of my flywheel,
but it should be the same as the one below. Just realized after looking
at that photo, that there probably wouldn’t be room to mount
a Evinrude type timer on the top of the crankcase, as the gas tank
mounts too close. Not sure what a "swing" timer is, but look forward
to your suggestions.
Thanks!quote JimParrott:Buccaneer,Do you have access to a lathe? I think a simple timer such as the ones used on inboard engines could be fabricated to take the place of the mag, or you could use a swing timer that would look more original. Please post a picture of the bottom of the flywheel. I will make a few drawings for suggestions. Having problems with posting pics right now and will be out of pocket til tomorrow..
Thanks
Jim
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I was thinking about how other magneto’s that have adjustable timing
advance "worked", and remembered that I had an old tractor magneto
off a Farmall F-12 in storage the last 36 years, so I dug it out and
it’s pretty "high tech" for the 1930’s in how it works.
The Farmall mag has a drum that the points mount to, that
rotates inside a bore. The drum’s rotation is limited via a pin in the bore
and a slot in slot in the drum. The cover engages the drum to advance or
retard the timing.
I don’t see a way to adapt the same idea to my magneto. I still think there must
be a way to rig up a movable contact points plate with lever,
but it’s not coming to me.
The Farmall mag is cleverly designed so the coil wire that attaches to the
points does not move or twist around. That would just be one
consideration.
Any magneto engineers "out there"?
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Buccaneer,
Attached are some pictures of some jump spark ignition timers. Using a buzz coil spark occurs when the circuit is closed via points or wiper. The first pick shows an early Lockwood that has a spring loaded plunger that contacts a brass contact placed in the insulated ring. The next two is a later Lockwood converted to modern points. Last is a Ferro that the cam lobe simply swipes against a piece of spring steel which is insulated from the timer housing. Castings for the Lockwood handle and plunger are available as well as the covers. I use micarta for the insulating ring and cam lobe for these timers. A simple one piece housing can quickly be turned on a lathe with a suitable sized round of aluminum and handle added. A mount could be fabricated from some .5 – .750 aluminum plate. A short drive shaft, with a set collar on the engine side of the mount. A wiper or point set up with a insulated contact, buzz coil, cover and mount and your good to go. I hope this makes since. My shop is across town and no internet there, if needed I can go take some timers apart for more pics if needed. Will post some buzz coil info in a little bit.
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