I have an old 3700 that belonged to my uncle and he let me have it and my grand-father's(RIP) Mac 10-10. I dumped the old rancid mix out pour in some fresh stuff and away it went. I put a fresh Oregon Pro-Lite b/c on it and it sings. I cannot wait to get it into to some serious wood. R|uns like a top, idles beautifully.
It always amazes me how some of these old saws can sit forever and then with just new gas fire right up while others it seems like they sit over night and nothing. Congrats on the two saws.