1816 Tecumseh engine question

[the.hogman]

Well I have rebuilt the axles, rewired the entire machine and several other projects so it is absolutely good or better than new. Now I am at the point of running it. This 1816 has the original 16hp Tecumseh motor and it runs great...when it runs. I am having the issue of it losing spark as soon as it gets warmed up (5 mins or so). It is not an issue of the engine seizing, fuel, or anything mechanically preventing it from running. It appears the ignition is breaking down as soon as it gets warm. I can come back an hour or so later and she will fire right up and run until it looses spark again. Short of replacing the engine with a B&S or something, does anyone know what I can do to fix this? I still need to do some testing with the ohm meter to pin it down to the igniton module or the stator but it must be one of the two. (on this Tecumseh motor these are the ONLY two things that make up the ignition) Did I mention Tecumseh is out of business and it is EXTREMELY hard to find parts? Your suggestions will be appreciated.

 

[CASE 1840]

I'm guessing this is the cast iron overhead valve engine correct? If so and it has electronic ignition, they are very sensitive to the gap between the flywheel pins and the sensor.
Tec is still in business making compressors / gearboxes and a couple of other things, they just got rid of the small engine business. There is a company that took over parts support but even when Tec was making engines, the cast iron line was decades obsolete.
I did see where someone used automotive crank position sensors as a ignition trigger and a GM module for spark control. They had 2 sensors to provide ignition retard during cranking to save the starter.

 

[the.hogman]

I'm guessing this is the cast iron overhead valve engine correct? If so and it has electronic ignition, they are very sensitive to the gap between the flywheel pins and the sensor.
Tec is still in business making compressors / gearboxes and a couple of other things, they just got rid of the small engine business. There is a company that took over parts support but even when Tec was making engines, the cast iron line was decades obsolete.
I did see where someone used automotive crank position sensors as a ignition trigger and a GM module for spark control. They had 2 sensors to provide ignition retard during cranking to save the starter.

Exactly, the old cast itron OHV. All of the magnets are secure and in position, the trigger pins seem to be at the right height levels and I have the air gap set to .008 The range was .006 - .010 Like I indicated, it runs like a top until it gets warm. I saw some conversion systems but it started me thinking about re-powering it. If I can find a simple economical fix that is the route I want to go, but if I have to, I guess I can bite the bullet and put in another engine... Do you remember where you might have seen the conversion write up with the GM parts? Thanks for the note and any other thoughts!

 

[willie59]

Exactly, the old cast itron OHV. All of the magnets are secure and in position, the trigger pins seem to be at the right height levels and I have the air gap set to .008 The range was .006 - .010 Like I indicated, it runs like a top until it gets warm. I saw some conversion systems but it started me thinking about re-powering it. If I can find a simple economical fix that is the route I want to go, but if I have to, I guess I can bite the bullet and put in another engine... Do you remember where you might have seen the conversion write up with the GM parts? Thanks for the note and any other thoughts!

If the plug is fired by a magneto under flywheel, it could be the magneto coil is going south. I had a single cylinder Wisconsin engine do this once, would start and run, but after it got warm would cluck out. Replaced the mag coil, all was well.