What are the symptoms of engine blow-by?

[OThomas]

The symptoms of engine blow-by are: 1. Decreased engine power; 2. Deterioration of engine oil; 3. Engine failure to start, with blow-by at the valve cover and white smoke emitting from the crankcase oil filler port. The causes of engine blow-by include: 1. Piston rings being misaligned, broken, or worn out, leading to ineffective operation and poor cylinder sealing; 2. Excessive clearance in piston ring gaps, side gaps, or back gaps; 3. Improper installation of the air filter or a damaged filter element, causing large amounts of dust and impurities to be drawn into the cylinder and resulting in wear; 4. Cylinder head bolts not tightened to standard torque, leading to poor sealing of the cylinder gasket and gas escaping from the engine; 5. Poor sealing between the valves and valve seats; 6. Severe lack of coolant in the cooling system, causing a rapid rise in temperature, adhesion between the piston and piston rings or cylinder liner, and extensive scoring on the piston surface.