Chainsaw Repair

I need some help, this saw won't idle when it gets warmed up and you cut a little wood. I don't know what model it is, I think all the numbers are worn off. I'm kinda new to working on these saws, but with some direction I can probably do it.

A good place to start would be to pull the muffler off and move the piston up and down real slow so you can see what piston and cylinder look like.   

That's a Husqvarna 2100CD or 2101XP.  Looks like it's had a working life.  It probably needs (and definitely deserves) a good going through.  I'd replace the fuel line, rebuild the carb, and replace the crank seals just as a matter of course).  All those rubber parts have given all that can be expected of them over the last 30+ years. 

Running the saw with leaking crank seals, a leaking fuel line, weak carb diaphragms, or some combination thereof...............WILL cause the engine to lean out and damage the piston and cylinder.  Running the saw with an improper tune (mostly having the H side set too lean) will do the same thing. 

I also see what looks like a zip-tie 'throttle lock' hanging on the rear handle.  I'll bet either someone doesn't know how to engage the built in throttle lock, or there are broken bits in the trigger and/or operator presence/throttle lock lever.