How to Determine if a Check Valve is Damaged?
2 Answers
Due to burrs on the edges of the valve core not being completely removed, the check valve gets stuck in the open position, or the clearance between the outer diameter of the valve core and the inner diameter of the valve body hole is too small. Burrs or impurities on the edges of the recessed groove in the valve body hole cause the Litian check valve core to get stuck in the open position.
I once experienced a faulty check valve in my old car. When accelerating, the car felt particularly sluggish, as if it couldn't draw in air properly. Upon closer inspection, there was a faint hissing sound near the valve, like an air leak. Later at the repair shop, the mechanic taught me a simple diagnostic method: remove the valve and try blowing air through both directions. If air passes freely both ways, it means the valve is stuck or can't seal properly - its one-way function has failed. A properly working check valve should only allow airflow in one direction (you shouldn't be able to blow through one side, while air passes easily the other way). After replacing the valve, my fuel consumption immediately improved. Leaving a faulty check valve unrepaired long-term may lead to increased engine carbon buildup or failed emissions tests. Regular inspections are recommended, especially for older vehicles prone to wear.
