I figured I'd post a link to The Chainsaw Guy. When I was researching a John Deere chainsaw my neighbor wanted to sell I came across his Youtube channel and ended up calling him. We spoke for about 15 minutes. He was a great guy and willing to give me a good run down of the chainsaw. When I mentioned an older Pioneer I had picked up he offered some information and said to call him as they were easy to fix generally. I haven't gotten around to calling him back, but will in a few weeks as I just picked up another older chainsaw and it needs a recoil spring.
Chances are if you are researching a chainsaw Rich has a short video about it on his channel.
The Chainsaw Guy:http://www.youtube.com/user/radougan120955
Myrtle Creek Saw Shophttp://www.myrtlecreeksawshop.com/