I have the snapper 21" commercial hi vac with the 6 kaw. The problem I'm having is its laying about half the grass down and cutting the other half, it sure looks like all of it has been cut but with a closer look the grass is still long and laying down like its been rolled. any ideas of what it could be ? I have already checked to following and it still cut the same sharpened and balanced blade (took it to the dealer and wasted $7 bucks) spotless underneath all wheel height adjusters set the same I bought this unit in the spring and have problem after problem with it and feel the unit was a waste of money. after trying the above with no results I had no choice but to take the old craftsman off the trailer and that old crapsman (as some will say) brought a smile to my face as it has in the past with its superior cut.