Carbureted Eagle Hit Miss

rdean

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I built an Eagle hit miss engine a couple of years back and it has performed well since. I run all my engines at least once a month to keep them in good condition.
I got to thinking how would a hit miss engine run with the hit miss disabled and a throttle type carburetor installed. I have only ever heard of one similar type engine and it was built well over 100 years ago with very little information available.

So here are a couple of pictures and a video of my experiment.
The rubber band is to keep the throttle closed.

IMG_0678.JPG

IMG_0679.JPG

Video


The very light intake valve spring doesn't close the intake valve quick enough and that causes some blow back through the carb.
This was just an experiment and I will probably put the engine back like it was.

Thanks for looking
Ray
 
Um, there were a lot of throttle governed engines that evolved from a hit and miss earlier model. The most prolific engine was the International Harvester Company model M, LA, and LB engines.
 
The main point of the experiment was to see how an engine that was designed with a intake valve that was sucked open by the down stroke of the piston and not using a push rod, rocker arm, or cam lobe would run.
I was surprised to get it to idle as low 700 rpms.

Ray
 
Yes, as long as there is good vacuum most engines will suck open their intake valves with no issue.

I bought a 53' Allis Chalmers CA some 10 years ago now. It was in really nice shape, had new rear tires, ran/idled well but would fall on its face when it as put into 3 or 4 gear or made to work. The price was good accordingly and the owner (a guy that rebuilt v12 packards as a side job no less?) was adamant that it was an ignition issue and had already replaced the distributor once and included it with the tractor. I had a guess it was a rocker arm adjuster loose or broken. Got home, pulled the valve cover, the valve lash had gotten loose, the push rod fell out and got bent. 10 buck including shipping and it was running like a song.

The reason it fell on its face, as you made the engine work, the governor opened the carb butterfly to add fuel and the manifold vacuum pressure fell accordingly. This then caused the cylinder to stop opening its valve and it would drop out.

You model engine obviously doesn't actually perform work so it will merrily purr along.
 
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