Grinding Noise?

When I go to start my mower it now makes a grinding noise until you release the key. I does not seem to be getting stuck. I gave it some WD-40 a week ago but it has not helped. Any suggestions?

Where's the the noise coming from? the starter?

If you don't know what is making the noise pull the cover off the starter and watch the engagement. Sometimes when you crank the engine the pulley turns the belts and they can make funky sounds depending on what they are connected to.

Is the starter frozen & not spinning? Smack it with a hammer (lightly), or is your battery dead/weak?

I had a similar problem, my yard mower started grinding when I cranked it, I found one of the starter bolts had come out and the other had come loose enough that it wasn't engaging the flywheel properly, not saying that's your problem just what I've experienced in a similar situation

Maybe your starter gear is stripped?