Primer ball on my mccullock line trimmer will not pull gas from other side of the carb.. i really dont like the design and im not sure i fully understand how it actually works.. primer ball on the return side of the fuel route.
Two questions. When you press the bulb and let go does the bulb stay pushed in. The second question is if the bulb comes back out can you hear what sounds like air being sucked from the center of the carb were the butterflies are when you pump the bulb. .
I have an Echo chainsaw that I converted to model airplane use. It refused to start after removing the engine from the saw.
I replaced the original carb with a Walbro off a Ryobi and it starts and runs fine. The "primer bulb" was labeled "purge valve" on the saw. I'm thinking the "purge valve" bleeds any air out of the carb, is this thinking correct?