The CHEAP Air Filter Is Destroying Your Portable Generator (Here's Why)

$600 of engine, a few hundred hours on it, and no compression left, killed by the cheapest part on the whole machine. This one takes apart how a cheap or badly sealed air filter lets abrasive silica dust past the media and into the cylinder, why that dust is harder than the metal it grinds down, and why the one number that would let you tell a good filter from a dangerous one, its filtration efficiency, is printed on almost nothing you can buy. The paper at the center of it is the air cleaner test standard the engine makers use in the back room and the parts aisle never prints on the box. On a 99% filter, 10 grams of dust reach your engine for every kilogram thrown at it; on a 99.9% filter, 1 gram. That's not 0.9 of a percent. That's 10 times the dirt, on a filter that costs about the same and looks identical on the peg.