Thanks everyone. The saw is a Dolmar ps-9010, older one, no primer bulb or compression release button.
I got the saw used in 2012, it had a 37" bar and new carb and fuel lines, ran great.
I used it on a 67" Alaskan mill for about 20 hrs run time before the piston fried, there was an induction leak on the rubber intake manifold.
I replaced the cylinder, piston, and intake, and have used the saw one to three days per week for two years without any problems at all. The saw has not sat idle for more than a month sense I got it. I am a full time artist/woodworker and ex aircraft mechanic.
In may 2014 I upgraded to a stationary Panther Pro mill, a chainsaw mill with a track and cairage like a band mill with a 42" bar. The saw cut like a dream for a few months, but started to act up, I thought, due to the sawdust discharge literally filling the carburetor housing. I had been removing the cover during operation to keep the air filter from clogging and was in the process of setting up a deflector to keep dust out of the housing when this problem started.
I thought the problem was in the carb, so I took it apart and cleaned it put it back together and it ran fine for a few hours. Same problem started again. Then it wouldn't start at all.
I took the saw completely apart and cleaned everything. She ran fine for a few hours then started messing up again. I did crack open the gas cap to see if the tank vent is clogged, checked the muffler too its clean empty and no screen, exhaust port is clean too.
I had been blowing out the carb with my compressor, 150 psi, a friend said that was a no no and I may have damaged the carb.
I got a used one off ebay put new diaphams and needle valve o rings on it (I had just done this to my old carb) and the saw ran fine for 45 mins of cutting, then same problem.
I had been tuning with a tach, but now that is now no op, so I don't know the current rpm. Everything seems to break in waves (I have 7 random orbit sanders and only 2 work at the moment)
So now I am here. Like I said earlier, I hate just throwing parts at a problem, so I thought I would see if any of you have any ideas or test procedures I could try.
Today is a heavy production day and an art market tomorrow, so Sunday Monday I plan to tear everything down and check each part, replace fuel and impulse lines, clean everything and put it back together.
This saw is a real work horse, lots of low end torque and cuts like a demon, I got it from someone who did not know anything about saws and I only paid $250 for it, so yes I do not mind dropping some more cash into it and get her back in service.
Thanks again for the input so far and any other help would be appreciated. I need to learn how to post photos here and I'll post some photos of my setup.