This mower sat in the garage for three years. Changed the oil and all the filters, cleaned out the gas tank new gas, new battery, new spark plug. It sounds like it wants to start but won't. The mower blade was bent but would still run when my grandma put it in the garage three years ago. I've had some of my friends tell me that it could be a valve if so is this a easy fix? Thanks

More than likely you just need to clean the carburetor. If it had gas in it when it was stored it surely gummed up the carb and probably has the needle valve stuck.

If the blade is bent the shear pin may be sheared. It will have to be replaced. Hope this helps.
Mike