Magneto Igniter Testing

[Tom Herd]

I am looking for a way to test a McCormick-Deering (IH?) 1.5hp gas/kerosene 1921 magneto/igniter. I either have fuel problems or electrical. I primed the "gas" filler hole in the carburetor (3-valves, gas, water, kerosene) opened the gas needle valve and started turning the flywheel,.... again,.... and again,.... nothing.
It probably is fuel related, but I really don't want to get into the carburetor without first eliminating the electrical.

[Rich Martz]

Try disconnecting the mag and see if it will run on battery and coil.........

[Chuck Parcher (Ks.)]

i always start mine on battary and coil then disconnect and switch to the mag before it stops running. you don't want the batt. and coil hooked up at the same time as the mag you'll damage the mag windings i've been told

chuck

[Tom Herd]

The battery and coil seems like a very good idea. I saw one coil for sale on eBay for about $40.00. I believe I should be able to find something else, that would work, an old transformer with the secondary left opened. Any ideas?

[Joe Morris]

You can use a coil from an automobile , the old round ones seem to work well and much much cheaper than the one on e bay. JUst go in on side of the coil and out the other and disregard the center /coil wire post. Run one wire from either post of a battery to one of the posts on the coil, then a wire from the other post to the ignitor, pos. or neg, it don't matter which. then run a wire from the other battery post to a good ground on the engine. IF the problem is in the fuel that can be one or more of several things. fuel pump check balls not holding. stopped up siphon tube/tubes to name a few. I hope this will help a little. good luck in a good hobby. Joe Morris

[Rudy]

I have found using a car air conditioning air compressor clutch coil works really well. they will run the engine at a show all day verses the auto coils which heat up and conk out after a few hours.just get a old compressor from a wrecking yard and rip the coil out.

[Ralph Leonard]

Tom, just about any coil that will produce a fat blue spark will work. I've used the primary winding of automotive and buzz coils, (block the buzzer on buzz coils), and starter solenoids. Experiment with what you have.

Momentarily touch the leads to the battery terminals and observe the spark.

If you have a ohm meter, select the coil with the highest ohm reading that gives a good spark.

[Joe Morris]

Tom, any coil you use will heat up if you are useing it on an engine where the the points are always closed and will soon run a good battery down . I run a 6 horse Fairbanks type "H" engine for hours, several days at shows and the coil has never heated up. BUT,the engine is designed so that the points are alwawy open except when they close for a fireing stroke. it dont hurt if you are only useing a coil and battery for starting only, on an engine where the points are always closed. Joe Morris in east Tennessee

[Dick Welty]

Tom,

I have used Auto coils as suggested above and old transformers and the new reproduction coils and they all work ok but if you find that they solve your problem then you might look for an old original Igniter Coil.

I purchased one on e-Bay for $9.95 + shipping that weighed 6 lbs and it puts out a spark that you wouldn't believe. It was miss-listed as a buzz coil that had been used on a 1907 Hicks boat engine. It was in a broken wooden box that looked like junk.

I took a chance on it and when I tested it I decided to mount it on new wood and it looks great and it starts my engines even when they are a little flooded.

[David Nicolson]

I have used a ballast out of an old fluro light on my 4hp yb stover and have found them very effective, another plus for the ballast is its size. Dave in oz

[Dick Graybill]

I've used a coil off a Briggs or Lawnboy engine.They are easy to hook up and have a very hot spark. Dick in central Pa.

[Ironman]

If you want to use something REALLY different for a coil, remove the stator from a junk alternator and use the stator for a coil. Ran an early 8 HP Stover for hours and hours using the stator for a low tension coil. And for those of you that THINK that I mean the armature, sorry guys but I DO mean the stator. Darn things might be around 6" in diameter, but they don't weigh much and they work great as a coil.

[Elden DuRand]

You can also use a starter solenoid coil. Get a 12-Volt solenoid (the kind that sits atop the starter motor). Find the two leads that make it pull-in. Now, either remove the spring or just wire the plunger to its inward (energized) position and have at it.

If you want to get fancy, take the solenoid apart down to the coil and plunger and make your own housing. The plunger acts like the core of the L.T. coil.

A better core would be a bunch of soft iron wires (mechanic's wire) a little longer than the coil bobbin, packed into the area where the plunger went.

Take care - Elden