I have a 5 year old L110. Just replaced the battery. Started and ran fine on 2 or 3 different occasions. Pulled up on a slope where the front wheels were about a foot higher than the rear and shut the engine off for a minute. When trying to restart got a single click then NOTHING.
Have "jumped" from positive battery terminal to starter bolt which barely turns motor... but it does move. Checked battery and it is fully charged.
Saw something in another question about the starter "binding under load"? Not sure where to go from here. Amateur with motors/engines/electrical things.

Update: I have rotated the engine backwards manually and am then able to get the engine to rapidly turn over and even start using a jumper from the positive battery terminal to the starter bolt. But once I turn the mower off I have to repeat the process. AND I can't get it to turn over using the key in the ignition even after manually turning the engine backwards.

Suggestions?

Check your fuse, and you may be able to lube the "candy cane" shaft on the top of the starter.

I have a 5 year old L110. Just replaced the battery. Started and ran fine on 2 or 3 different occasions. Pulled up on a slope where the front wheels were about a foot higher than the rear and shut the engine off for a minute. When trying to restart got a single click then NOTHING.
Have "jumped" from positive battery terminal to starter bolt which barely turns motor...but it does move. Checked battery and it is fully charged.
Saw something in another question about the starter "binding under load"?? Not sure where to go from here. Amateur with motors/engines/electrical things.

Update: I have rotated the engine backwards manually and am then able to get the engine to rapidly turn over and even start using a jumper from the positive battery terminal to the starter bolt. But once I turn the mower off I have to repeat the process. AND I can't get it to turn over using the key in the ignition even after manually turning the engine backwards.

Suggestions??
The fuse was fine. What do I have to do to lube the starter shaft?

Remove the dust cover, and spray a good lube up on the pinion gear and shaft. I personally prefer PB BLASTER. Try that and see if it will help.