Blades for a 2009 craftsman lawn tractor will not work

This may be due to worn out piston rings or overfilled oil.

Look to see if the belt has come off the deck. Also, does the handle that engages the blades have tension on it or is it loose?

There are four pulleys on the deck. Two for the blades, one idler, and one tensioning. The two smaller ones are the idler and tensioning. The tensioning is the one on the right. The post coming out the top of the pulley is where the spring goes, it slides over the top and a clip goes throught the hole at the top of it to retain the spring.

I hope this helps.

Check your spindles, especially the shafts in the spindles. If one of them is bent, it'll make the blades vibrate as they spin. You can find replacement shafts and spindles at Partsbuggy.com.

If you have an electric pto switch, the switch, connecting wire from the switch to the pto clutch, or the clutch itself could be defective. You can check the switch and wire with an ohm meter. You can also check for proper voltage at the pto clutch plug.

Check the oil, if it is a milky color then it has water in it and will cause it to over heat. Also smell it for gas that will also cause it to over heat. Has any other work been done recently?

sounds like either the spindal bearings are shot or maybe the spindal shaft is bent. check for up and down slop at the blades. then turn blades towards each other and check that the heigth lines up. also chec the idler pully to make sure it is not slapping around.

You might want to check this may sound silly but check to see if the blades were put on upside down.

It sounds to me that you need a new mower deck drive belt, or your blades need sharpening. If the blade edges are rounded, they won't cut butter... Also, when mower is off, check mower deck drive pulleys to make sure you don't have any that are locked up or are dragging. You can check this by pulling the belt away from pulley and spinning the pulley by hand. MOWER MUST BE OFF before attempting any of these checks. You would be surprised how many people would try this with the mower running.
Hope this helps

have you tried the safety switches?