hi,yes its a powertorque engine,i replaced the starter o ring the primer cover o ring as well as the intake and manifold o rings.also put a new kill boot and plug on it. gave her a full service its been well over due for a while,its always revved a little hard but now its gotten worse.all hoses are fitted correctly,from the info you supplied(thanks for that)and the carby has never been changed out.so saying all that maybe it is the bottom seal,how would i check that?thanks.