Went to move my exc. today to a new job and it wouldn't spin. You can see the house bump against the gears on the drive motor but when I move the lever to turn it just pulls the engine down and does nothing. Is there some valve that could not be releasing causing this. Also the throttle will only come up to about half throttle. It was working fine but it has been setting three or four weeks. I did change the starter while it was setting but this surely wouldn't have anything to do with these problems.