Stihl BR340 bogs down when warmed up

[deminin]

My BR340 backpack blower starts and runs good for a minute or two when cold. However when it warms up, it bogs down badly at full throttle. I replaced the fuel filter, air filter, and spark plug...no change. I removed the muffler spark arrestor...no change. I bought an aftermarket carb kit on EBAY, replaced the carb....and no change. I noticed a small fuel leak around the fuel line grommet on the gas tank, so I replaced the grommet and fuel line....again, no help. I use 91 octane, no ethanol gas, and 50:1 mix, and my other Stihl tools....chainsaw, trimmers, etc., are all running good on the same can of fuel...cold or hot.

Any suggestions on what I might try next???

 

[deminin]

Never mind...I figured it out. There is a "air" hose going from the air filter housing to the gas tank....allows some air pressure to build up in the tank. There was some sort of "obstruction" in that hose....not allowing enough fuel pressure to the carb at full throttle. I replaced that hose, and everything is back to normal....ran the blower for a good half hour with no signs of "fuel starvation".

At least now, the blower has gotten some pretty thorough "maintenance" and I have a spare carb, etc.,