Perfect circle piston rings play a much bigger role than just being perfectly shaped and circular in an engine. The shape strength, wear and gap between the edges are all aspects that must be considered when installing new rings in to any engine. Being able to choose the correct rings required to install in to an engine during the rebuild is the main challenge during engine rebuilding.
Without being able to physically and mechanically measure the engine components being changed and the suitable piston ring gap required when the ring is squeezed inside the sleeve could mean that an engine will over heat and break the brand new perfect circle piston rings or if too loose than the engine would begin burning oil that would seep in to the combustion chamber from under the piston.
Since marine engines are under more pressure due to the floating vessel, engine failure at sea could be disastrous if a vessel were to loose its main engine in rough seas.
For this reason marine engine engineers go the extra mile to make sure that the piston rings and other components fit exactly on the engine to provide maximum thrust and lifetime to the engine and vessel.
Engine failure out at sea is common but not very life threatening if the water remain calms, most vessels will have a back up engine that would be started to continue to the next port. The backup engine in many cases is smaller and only used for back up meaning if the vessel is cough in rough sea at the time it may struggle to fight the strong waves that push the vessel adrift.
Piston rings can only be considered perfect if they meet the measurement criteria require, any tighter or looser and the rings would be rendered useless. A simple technique used to check piston rings is by inserting the ring in to the piston sleeve and observing how much gap is left on the two edges. The gap would depend according to the piston size but it should be not larger than a few millimeters wide.
This gap prevents later seals as the engine warms up making a tight but smooth running surface in the piston sleeve. The grooves on the piston where the ring sits must also be cleaned and the measurement taken since the ring should have minimal plays to the side or up and down in the groove.
There are many different measures that must be taken to ensure the engines smooth operation and it would be difficult to explore all but basically what it means is that just having perfect circle piston rings does not ensure you will have a smooth running engine and many other factors must be considered to have reliable engines.
Perfect Circle Piston Rings,
