I was given a husqvarna 55 rancher that someone ran straight gas in. I replaced the piston and cylinder and now the saw will idle but I have no high end.It dies as soon as I pull the trigger.However I can sometimes get high reves when I turn it on its right side.The carb was rebuilt about a year ago but sat that long before the replacement of the new piston and cylinder.I also replaced the intake rubber tube and the impulse rubber seal.I am at a lost as what the problem could be. Any help would be much appreciated.