i have been reading about taking the carb bowl off and cleaning the jets but i have something attached on the bottom of my carb bowl that has a wire connection going to it. i have disconnected the wire and tried to unscrew this to no avail motor info is Briggs and stratton 14.5 OHV I/C quiet model-237707 Tyoe 1224-e1 code 9590512ze Can anyone shed some light please

Hello, I bought a Craftsman Lawn mower (mower specs below) that the previous owner cannot start. He told me that he was mowing and hit a stump then the thing sputtered and died. Of course thinking that this must be the flywheel key, I bought it ($25). While removing the engine shrouds, I noticed that a mouse ate the insulation off the SAM wires. I checked for spark and nothing. A new SAM was installed, and I was able to get spark, but still no fire. I removed the flywheel and the key was ok. I checked the carb, the fuel solenoid is clicking when the key is turned to run. I sprayed starting fluid directly into the carb, still no fire. I removed the bottom of the carb thinking that there might be crud, but everything looked ok. For fun, I removed the valve cover and the valves are moving when the motor is turning over. I did notice that the exhaust valve has a little clearance between the rocker and the valve stem. The intake is tight. There is no adjustment on the valves. I would need to remove them and grind down the stem. I am at my wits end. The Kohler service manual states to remove the white (kill) wire from the machine harness to eliminate the kill circuit. Doing this killed the spark. I even tried to take the red wire from the SAM and directly connect it to the positive terminal of the solenoid - still nothing. Any Ideas? Craftsman 16.5HP Mower Model No 917.271141 Kohler CV16S Spec 43527 Thanks - Mudder409