hello i just recently bought a 28 spl (not to sure of the year yet, no manufacter plate) and it was sneezing when i bought it so i rebuilt the carb and it ran great. after about 8-10 hours of running time it started sneezing again. thinking of replacing the fuel lines? also just found fuel coming out of the primer solenoid(maybe bad o-ring) when i open the manual shut off valve all the way. also a very small crack on each side of the shut off valve plunger which basicly pulls straight out of the solenoid and is sealed by an o-ring(as i mentioned earlier). i plan on replacing the plunger just wanted to know of any ideas i can look for or any advice that will save me time and money(which i seem to never have enough of) thanks for any help.