Piston and Liner

The cylinder is a key part of the engine. In a reciprocating engine, the cylinder is the space in which a piston travels. Depending on the structure and type of engine, the cylinder can be lined up in a vertical or in a V-shape

Cylinders work in extreme conditions, subject to high temperatures and pressures, difficult lubrication mode so often have the following damage:

  • The work surface is worn horizontally unequally to create oval. Harm increases the leak between pistons and cylinders causing reduced engine capacity
  • The vertical work surface is not equal to create a taper. Harm causes leaking of gas in the combustion chamber, degenerated lubricating oil, destroying oil film, lubricating oil on the combustion chamber, reducing engine capacity
  • In addition, the cylinder is scratched, the work surface of the cylinder is burnt and chemically corroded. The cylinder sometimes cracked





Piston is part of engine. For diesel engine, pistons are tasked with the cylinder and cylinder head to constitute combustion chamber. Piston gets pressure due to expansion of flammable gas and then transmits force to crankshaft to process during explosion and gets force from crankshaft to process intake, compression, combustion, exhaust (in 4-stroke engine).

Some causes of piston damage:

  • Piston skirt: to get worn by friction with the cylinder wall, reduced diameter change in taper and oval, leak between piston and cylinder increases, unstable moving piston in cylinder causes impact in the process of working
  • Piston ring groove: is worn by impact with the piston ring in which top compression ring is worn the most
  • Wrist pin: beveled or oval due to impact with the piston pin
  • Piston crown: normally, the top of piston is burnt, chemical corrosion due to contact with burning gas, in addition, piston skirt is burnt, scratched in dirty oil, sometimes piston also cracks due to engine failure or detonation
  • Piston pin: to get worn-out pins increase the gap with the bearing causing impact when the engine is operating under heavy, incomplete lubrication conditions.




With many years of experience in maintenance, repair as well as supply marine spare parts. Please contact to us for advice on the best repair and replacement options at the cost reasonable:

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