Just got this recently acquired saw running and now another problem. For some reason the fuel tank is being pressurized to the point fuel is spraying from the cap. The higher I rev the saw, the greater the spray. Swapped cap with a known good one. Not as bad but still unacceptable. What is causing this?
Pioneer P39 spitting fuel
- Thread starter johninky
- Start date
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Don't recall the fix but the saw is currently running great.
What is your tank vent like? Do you have a fuel cap with a bronze sintered metal vent in the centre of it? If so, these vents will let air go in both directions so it could be normal for fuel to be forced out with a full tank. Put fuel in a container and shake it (running saw) and pressure will build up and it isn't until the fuel starts to get used up that the pressure in the tank will change to a vacuum and start sucking air in.
Likely had a rubber duck bill that rotted away.
