Puncture holes can also come from flying rocks from the cutting head or if you dropped the trimmer against a sharp object.
Weed eater gas cap vent.
This article will help you make sense of replacing the fuel tank vent on an echo trimmer.
When the pressure reaches a certain point defined by so many pounds per square inch the valve opens by a very small amount relieving some of the pressure.
The vented gas cap has a one way release valve that is pressure activated.
Inside the cap is a rubber seal which can get lost at a refueling stop causing gas to start leaking.
Fixing things makes sense.
Clean the fuel tank and engine with soap water and a rag to help you better determine the source of your leak.
How to replace the fuel tank vent on an echo trimmer model srm 225 find official echo trimmer parts that fit.
The vented gas cap is designed to vent small amounts of air into the car gas tank line.
Then stops after another 5.