Hello all, Neep help with Briggs and Stratten intek motor horizontal single cylinder Model # 31c707 Made in 05. Motor is missing and backfiring at mid to high rpm's and runs smooth at low idle. Problems started after it was ran out of gas. Filled with gas and started and used it for a couple hours. Came out next day and unbeknownst to me the gas had drained into the crankcase through the carb and intake valve,, I started it and it spit and backfired for a few seconds then killed the engine knowing I had an issue. Upon inspection found the carb dirty and thought needle was stuck open so cleaned it thoroughly, (several times now) and started it back up and hasnt ran right since. I have ordered new float needle and gaskets for carb , no results, I have adjusted the valves, checked the compression which seems high at 120 lbs and holds compression. all springs are attached to carb linkage but when the motor misfires the throttle labors back and forth. I have a video but for some reason this site won't let me load it. I believe the original cause is the solenoid under carb bowl was sticking in the down position and allowing the gas to flow through. Nikki carburetor with new needle and gaskets. HELP!! I could possibly load video to you tube if it would help.
Thanks
Steve
"I believe the original cause is the solenoid under carb bowl was sticking in the down position and allowing the gas to flow through."
Has nothing to do with gas getting into oil. That solenoid only shuts off the gas to main metering jet has nothing to do with, "allowing the gas to flow through." Your symptoms indicate lean running. Probably need to clean carb - might get some improvement by running SeaFoam per instructions on can.
