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What causes cylinder liner cavitation?
Cavitation of the cylinder wall begins when air bubbles remove the wall’s oxide film, which protects the metal from coming into contact with oxygen and corroding. Flexing of the cylinder wall (after fuel combustion) causes the cylinder liner to vibrate, and creates vapor bubbles in the coolant.
What causes cavitation in a diesel engine?
In a diesel engine, cavitation is created when the cylinder walls rapidly expand and contract under the immense pressures created in the cylinder. In effect, this cyclic motion creates a vibration that causes a small vacuum pocket to form between the engine coolant and cylinder wall.
Why do wet cylinder liners protrude?
The main purpose of cylinder liner or sleeve protrusion is to give you the proper amount of “crush” on your cylinder head gasket. This ensures that once torqued, your cylinder head crushes the gasket evenly and to the correct specification.
What is added to coolant to prevent cavitation?
The nitrite or molybdate will form a thin protective oxide film on the coolant side of the liner wall. This oxide film, which is formed by reaction of the nitrite or molybdate with the liner wall, acts as a protective barrier to prevent corrosion and cavitation (pitting) from occurring.
Where does cavitation erosion normally occur on a wet liner?
Cavitation erosion is often found in diesel engines on the exterior walls of wet cylinder liners. The amount of erosion and decay will vary from engine to engine and may also vary from cylinder to cylinder. Vertical strips or patches of decay often form outside the cylinder corresponding with the piston thrust face.
What is the difference between wet and dry liners?
The dry liner does not come in contact with the coolant. Instead, it fits closely against the wall of the cooling jacket in the cylinder block. With the wet liner, the coolant comes in direct contact with the liner.
How does cavitation cause damage?
Bubbles form during cavitation. As the pressure in the pump increases, those bubbles collapse in the form of an implosion – equally as violent as an explosion. The implosion causes shockwaves to travel through the liquid and hit the impeller causing mechanical damage.
Which of the following ingredients is added to diesel engine coolant to prevent cavitation?
Fully formulated conventional antifreeze uses nitrite, which coats the sleeves, to protect against cavitation. Organic-acid-technology antifreeze uses chemicals that plate sleeves with a thin protective layer, but these formulations also may contain nitrite.
What causes a dropped liner?
Dropped liner failures are often associated with overheating incidents — either because they caused the incident or because the overheating caused the liner to come loose. As a result, you should take any overheat or near-overheat situation very seriously.
What is the name of the tool to check liner protrusion?
OTC’s Cylinder Liner Height Gauge Set helps you set cylinder liner protrusion to exact factory specifications. Dial gauge accurately measures cylinder bore flatness and depth. Hold-down bar correctly seats the liner into the block for accurate measurement of liner protrusion.