Seeking help to get this Powerhouse over the last hurdle

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Mburham

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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
 

Attachments

  • recorded-113733386506964.mov
    9.8 MB
  • Compression BounceBack.mov
    1.3 MB
  • Carb Replacement for Vapor Tank.jpg
    Carb Replacement for Vapor Tank.jpg
    1.4 MB · Views: 6
  • Vapor Tank Air Mixture.jpg
    Vapor Tank Air Mixture.jpg
    1.6 MB · Views: 3
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