I am new to this forum and joined since I could not find anything to help me diagnose my problem.
Yesterday while I was mowing the engine sputtered a bit and died. I tried cranking it again...it turned over but died. I checked the fuel level...it was a little low but not enough to uncover the pick up and get air in the lines. Decided to top it off anyways and tried again. This time the engine wouldn't even turn. Figured either a seized engine or dead battery from trying to crank. Checked the oil level, it was fine. Hooked up the battery to my car... tried again still nothing.
Opened the hood to check if I could spin the engine by hand clockwise and nothing...it couldn't move. Tried spinning the opposite direction and it spun well for nearly a full rotation until it hits a hard stop. Turned it clockwise again and again it can nearly go a full rotation but hits a hard stop.
Next thing I did was open up the valve cover to see if both the intake and exhaust valve open. Only the bottom valve moves when rotating the engine.
Not sure where to go from here to troubleshoot. Help is greatly appreciated!
Sounds like the valve seat has come loose & is now out of place holding the valve open and the piston is hitting the valve , a stuck valve will also create the same symptoms ,
Or the pushrod has dropped off and is jambing the crankshaft
So it is off with the head
