I'm 100% with robertN on this one, for MIX ratio, mix per the OILS manufactures specifications. not as much the equipments manufactures spec.
running 2 cyc with out oil will cause it to loose the lubercation it needs internally, from piston & rings to seals & bearings. that much cutting probably shortened it;'s life, like others said now adding MORE oil won't help at all, damage is done, only make sure to not doing that same thing . use seperate cans, I use 2 different 1 gallon gas cans for my chainsaws/weedeaters. both use same oil (poulan synthetic stuff) even though the weedeater is a homelite. I buyt the MIX in quart squeese botles, and put the oil in prior to the gas, fill one can only when the other is nearing empty, this way I always have a full gallon of mix. nearing end of sawing season entering weedeater season. so I always have a good gallon of gas. they poulan stuff also has gas extender type additive to prevent it from going bad as quick.
also this means I nnever fill these 1 gallon cans up with cheap gas, I put in mid grade gas not the 86/87 but the 89/90 stuff. I've run the tar out of all of these machines cocmpaired to a normal home owner/farmer so far they fire right up easy as pie. I wore out 3 bars on one saw and have 8 or so chains in rotation used ti for cutting Rail road ties and soft maple. it cuts it all, but trust me when I say I tie is something that is HARD on em. even worse was the SPIKE I hit in one /forums/images/graemlins/crazy.gif
mark M