Well, i got a bluebird aerator a couple weeks ago. I have only ran it over three lawns, but might have a real big lawn coming up to do, so i want it working perfectly. Anyway, what its doing, is instead of pulling the plug of soil out, and spitting it out like it should, all the soil just packs into the "reel" that holds the "tines" onto the machine. So i end up with a nice and plugged up aerator. I dont know if it affecting the penetration or not. It doesnt seem to pull real deep plugs though. So, is there anything i can do to fix this? I dont know if it is a real big problem as much as me just not being happy as i dont think it is "right". I am kinda wondering if maybe it might have the wrong tines on it? Anyway, thanks for the help. BTW, it is a 424. It is about 6 years old, originally was a rental machine for Home Cheapo, if that means anything.