I really don't understand this replacing stuff on a saw before you even run it.
And, if it takes you more than about 10 seconds to tell whether a saw has any serious issues you should take up knitting.
It's pretty much my standard operating procedure to replace fuel line, impulse line, and fuel filter on any new-to-me saw that I'm going to run.
As for the knitting comment, you should really consider your audience before you post something like that. You just might be directing it at a very large combat vet with serious anger issues.