My solution was the same as Mary Louise's. I replaced chain, bar, and sprocket (which appeared to be pretty beaten up), and increased the chain oil flow from medium to high. I am still put off by the tension adjustment travel being half gone even with all new components, but at least the chain is no longer stretching like a rubber band. Thank you all.
I have the same saw, and the same problem as Mary Louise, and am a bit confused by your explanation of the numbers on the bar. The numbers on my bar (which is original) are 3/8 72 DL 107799 NF Assuming the 3/8 is chain pitch, this appears to contradict your saying that it should be 68 DL for 3/8 pitch. My replacement chain is an Oregon D72, which has 72 drive links and is 3/8 pitch. How does one determine the pitch of the sprocket? I'm not over-tensioning, and the chain oiler is oiling as it should.
I've had this saw for a couple years, and am quite pleased with it, except for the tension adjustment being half used up with a brand new chain.
What am I missing? Any clarification would be much appreciated. Thank you.
Lou