I had a little problem with 4 year old use very little but way was use may been cause coil over heating I run full throttle until gas ran out fill run again four time on hot day coil went out. before went out it would Idle down some and then rpm's to high because missfiring load crankcase with gas. New coil came with washer that insolate heat transfer from block and I add better cooling practice to operation HS 85 mounted on 2x4 to cut tops out 6 acres blackberries.

Sounds like the carb is not pumping up enough fuel.
Probable causes: 1. Partially blocked impulse passage.Remove the carb.On the black carb mount there is a small hole.Blow compressed air or use a cleaner to make sure this passage is clean.If it is clean, when a few drops of oil are poured into the hole, and the engine cranked over, the oil should shoot out.
2. Pumping chamber blocked.Remove the bottom cover (held with one screw).There is a tan colored diaphragm.Lift it off the cover.If there is any tarry stuff below, clean it off.
On the carb body, there is a small circular well which has a mesh.
Prise the mesh out gently and clean it.
Apply oil to the carb body and gasket and refit the cover.
3.Metering chamber blockage.Open the top cover with four screws.Refit the carb in on its mount.
Hold the metering lever down and crank the engine over.
If everything else is fine gas should shoot up thru the inlet needle.
Refit the cover.At this stage I need to know the type of carb you have.If the blower is old, it has a 3 screw carb without limiters.If its a fairly new blower there are limiter caps on the adjustment screws and there is not much that you can do other than opening the 'H' and 'L' screws to their stops.
Try starting it now.
Don't go to full throttle at once.Take it to partial throttle first and gradually increase the throttle.
And, do all this without the filter elements.

Joe