i have the ys 140. had some problems the first couple of tanks. the spring was on the wrong side of the pump diaphram. after fixing that. it's had 6 plus gallons of fuel thru it. the only thing that i've done is adjust the valves. it still pulls great. would i buy another? yes. it's not a pnp motor you have to learn it. every motor is just alittle bit different,