Okay, I'll be the first to admit that my saw is not exactly top of the line and the fact that I am still a novice with it but I'm having a problem with my saw. I have a Poulan Pro model PP4218AVX. The problem is that I am dulling the chain almost immediately after starting to cut. When I say immediately, I mean after about the 4th cut into white oak that's about 14" in diameter I am really having to work the saw to get through the cut. I have replaced 2 chains and the same thing happened both times. Can you more experienced guys give me some ideas as to what is going on here. I have a full reservoir of bar oil and it does seem to be oiling the chain. I just don't know what is happening.