High Compression on GX250

I am working on a small, fabrication shop made, asphalt roller that utilizes a GX250. 
I am running into a no-start condition where using the pull chord is very difficult and using the starter fries the battery really fast. Removing the spark plug alleviates these symptoms. I checked the valve lash and it is fine. i also watched to see if the compression relief valve was operational and the exhaust valve does seem to open at the end of the intake stroke as it should. I disconnected the engine from the asphalt roller's hydraulic pump to verify that it wasn't getting hung up by it.
I'm at a loss of where to go from here. Any help or advice would be appreciated