ACDelco Professional Engine Oil Filter PF63E - Walmart The “E” in the oil filter model means it is an E-Core filter. If you look on the inside of the filter you will see it uses a black plastic frame to hold the filter paper back. That might allow more oil flow since it is more open compared to the non E-Core filters which use a metal tube with holes. Amazon : Briggs & Stratton 40 Micron Fuel Filter I put the filter in and after a month the engine wouldn't keep running. The filter was only letting a trickle of fuel to pass through it. I purchased a new filter at the local Walmart, and the engine is running fine. I cut open the defective filter and didn't find any dirt or foreign objects. The fuel was checked, and it is fine.