I think if you leave the fuel cap tight when not in use pressure builds up in the tank. At least it does on my two-cycle equipment. I always loosen the cap a little when i'm not using them.

We just recently started stocking the Red Max hand helds so can't tell you about longevity but Red Max has always had pretty good stuff in the past. Judging from percieved air flow out the nozzle the BG 85 puts out more air. Carb problems and ignition coil problems have plaqued Still blowers in recent years, in dry climates like we have here in Vegas. Not so much in wetter climates. Areas with a lot of static electricity reak havoc with many coils on many brands of blowers these days. Most newer models are using multi stage advance igniton systems which can have their control modules popped by static that is created in the blower chamber. Everyone is working on a fix, some have done better then others, all have made improvements from 3 or 4 years ago. Most of the better brands have a life time warranty on coils, for the part only, once regular warranty is gone. Coils automatically have a 2 year full warranty because they are part of the regulated emission components. So aside from some potential down time you probably won't lose anything cash wise if one gives up the ghost on you. Most of the Stihl carb problems have been corrected and even those that crop up about 95% are discovered at intitial start up by the servicing dealer at purchase time. We have had some carb issues on Red Max trimmers that happened within a couple of weeks of purchase. These are lean throttle up hesitations that don't seem to show until the engine has broke in a bit. RM is aware of the problem and we just replace the entire carb rather then fix them. None of these problems are exclusive, we see them with Echo as well. Its all a matter of the manufactures trying to keep up with emission regs much like the automotive industry did in the 70's and early 80's. Only computer controlled electronic fuel injection really got most of the bugs worked out while restoring power lost. Count on it, one of these days your 150 dollar blower will have 500 dollars of emission equipment on it.

Casey : Do not have current info on this Saw , but you may well be correct within the air vent , if so normally a Duck Bill Valve is used numerous saws for this reason . It allows atmospheric pressure in but closes against reverse fuel flow. Perhaps self proclaimed Stihl expert Fish can advise of availibility of a Current Download . Good Luck Dude !

The lack of power and 'gunk' suggests the mix or carb settings are too rich. Are you mixing fuel at 50:1?