Filter medium looks thin and weak. Probably around 0.40-0.45 mm. When I calculated the leakage through a 25 sq. mm hole I got some terrible numbers around 40-50% at the delta p = 1.1 bar. In your case, the shape and the size of the holes is unknown. Just guessing that the leakage was 5-20%...
I have 2 more. And I wanted to see how long I can run them. Normally I run filters at least for 25000 km. I doubt it's safe for these filters and I am going to cut it to 12500 km or less.
I tried to do an unscientific test to see what gives higher air flow resistance: either the cylindrical surface or the flat surface. First I assembled the spring and the cartridge in such a way that there was about 0.5-1 mm clearance to the flat surface. The air escaped like there was no...
It's has been sitting around for a few years. The filter medium feels a bit flimsy despite being quite thick of 0.6 mm. The thickness partially comes from the fluffy material which doesn't provide any strength.
Fram XG6607.
It's a perfect filter with no weaknesses.
The ADBV is 100% hermetic.
One of the end plates has a seal which works great.
A flashlight test shows that the seal is perfect.
The filter medium area is about 440-450 sq. cm.
No pressure on the spring. I doubt that applying pressure would close the gap even by 0.1 mm. The spring is tight inside the cartridge (because of 4 indents on the cylindrical surface) and doesn't move easily.
I tried to evaluate how much oil gets bypassed under different conditions and in the worst case scenario when the medium is totally blocked/loaded with the dust. First I tried to calculate myself. The result I got was suspicious. I checked again and again. Then I tried the Pressure drop online...
The hole is about 0.5% of the total medium surface. It really hard to evaluate how much oil would leak without knowing the coefficients of flow resistance though the medium and through a slot of only 0.3 mm wide. Likely the oil flows a lot easier through an equivalent square hole of 5x5 mm.
I wanted to see what's inside a Champ made filter and how good it is as couldn't find any useful and detailed info.
A flashlight test. Pretty significant dirty oil leak according to my calculations. It's like having a 5x5 mm hole. I'd guess 1-2% of oil gets past the medium unfiltered.
The ADBV...