Seeking help to get this Powerhouse over the last hurdle

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Oct 22, 2023
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I am putting the finishing touches on a Jerry Howell powerhouse and I just can't seem to troubleshoot this thing effectively. I get good bounce back when the piston compresses the air, so I am inclined to think it is not valves. I had some issues with initial leaking around valve bodies, so I pushed out the metal ones and replaced with brass, which improved the sealing. The spark plug is ignited with an RCEXL unit, sensing the magnet with a Hall, and it set to fire at TDC when the timing lever is all the way up, and then I can advance it by moving the lever down.

I had issues running it with the carb. I was initially flooding it a bit, so I swapped over to a vapor tank configuration using a small mason jar. The air draws in and agitates the fuel, currently running camp gas/napthtpa. I tried kerosene to no success. I can get it to fire under "drill power", but not effectively enough to maintain its running state. While running it with the drill, I am able to adjust the air/fuel mixture knob to where it doesn't fire in either direction, so I assume I can adjust into the "too rich" zone and all the way to the "too lean" zone. I weakened the intake spring, and it visibly sucks in on intake as well as providing a nice little audible fart. I will try to nab a video of that if its any help to the community.

It's not mounted to a final board and ignore the DC motor... that's a work in progress for a starter/generator. Final state will be a key ignition that will turn on an Arduino, power up an LCD tach, flip some relays to route the DC motor to a starter, then once its running, the relays revert and flip the polarity in reverse to turn the DC motor into a small generator to charge some goofy USB cable or something.

Curious if anyone has some "things" or "tricks" to help isolate the root cause. I am leaning towards air-fuel mixture, but when I threw the vapor tank hail mary, I exhausted my easy button. My other thought, is maybe going with the buzzcoil electronic ignition board and ditching the RCEXL. Any feedback is going to be much appreciated!

Michael Burham


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