Jan Ridders Otto 4 stroke build

[madjackghengis]

Great job on that engine, it looks beautiful, sounds very smooth, and runs great, and I think the visible vapor carb is a great addition.  A very fine job, very well done. Jack

[dbvandy]

Thanks for the kind words, guys...  I love the visible vapor tank!  It is the number one conversation piece when I am explaining the engine to people.  All the gear heads wonder how it can run without a "proper carburetor", however, after I tell them the physics of what is going on, it makes perfect sense to them.  

I think I will make one that I can use for my new engines just as a "test bed" vapor tank so that I can fine tune other aspects of the engine like valve and ignition timing without having to worry about the fuel system.  The tank is VERY forgiving on settings and looks cool as well...

Just in case you have not seen it, I have started a thread on the V4 at:

http://madmodder.net/index.php?topic=4577

Thanks again, I loved making this engine.

Doug

[cfellows]

Nice build, Doug.  The finished engine looks stunning.  I'm curious about the weed eater coil. Does it have points or electronic circuitry built in?  Or is it just a coil activated by the magnets on the flywheel?  If the latter, I'm surprised the will generate enough voltage for a spark.

Chuck

[dbvandy]

Nice build, Doug.  The finished engine looks stunning.  I'm curious about the weed eater coil. Does it have points or electronic circuitry built in?  Or is it just a coil activated by the magnets on the flywheel?  If the latter, I'm surprised the will generate enough voltage for a spark.

Chuck

Thanks for the kind words...

What you see is all that is there, just the coil and lead wire.  I used two neodymium magnets on the flywheel, maybe overkill, but I had them from a previous project.  The coil produces a BRIGHT blue spark all the way down to about 500 RPM, then it fades away.  This is not an issue, because the smaller and lighter flywheel I used can't really get the engine around to another compression stroke at that RPM anyway (tons of compression with the Viton o-ring). It is the same coil arraignment used on my Webster and it works beautifully.

It is strong enough that I have been zapped a few times pretty hard by accidentally touching the kill pin on the coil while holding the engine.  Not quite a tazer, but I did let go of it very quickly!

Doug