The car engine has pistons and this are equipped with two separate compression rings toward the crown of the piston, an oil control ring assemblage toward the skirt. The rings moves in an annular grooves in the piston. The compression rings help to harness the power being produced while stopping unwanted gases from having access into the crankcase. The oil control ring assemblage removes excess oil from the cylinder walls to prevent the oil from entering into the combustion chamber. The inability of this rings to function could result to a lot of problems. As highlighted below
BAD COMPRESSION RINGS
The signs of a bad or broken compression ring will immediately show in the form of loss of performance, and in most cases a dead miss in the affected cylinder. A broken rings will be unable to hold the combustion gases and will result in blow-by gases entering the crankcase and going out from the positive crankcase ventilation system. PCV valve will most likely be located on a valve cover. Ensure the breather tube is disconnected from the PCV, and if there’s a strong and smoky flow from the valve, then it could be that compression rings are broken. Apart from performance loss, other problems can surface over time. Partly burned fuel blown by the engine rings, sulfur in the fuel mixes with some water traces in the oil, combines to form sulfuric acid, that damages the internal components of the engine. Be sure to the compression using a compression tester. A normal compression should be around 160 to 180 psi, with no more than 15 percent difference between the cylinders. If the compression is low on one cylinder, there may be a broken ring on that cylinder.
BAD AND OR BROKEN OIL CONTROL RING
This will be noticeable by the quality of the exhaust smoke, this will turn blue and have an oily smell. The exhaust will send off blue smoke per revolution for the bad cylinder, and good-looking exhaust for the other good cylinders. These blue smoke helps in diagnoses. There could be oil shortages where there are no cases of oil leakages.
Apart from the damage caused by blow-by gases, there may be shown mechanical damage. The ends of the rings can cause a hole in the cylinder wall, stopping the other rings from having the right contact with the cylinder walls. The annular ring grooves in the piston can be bad, and since the cylinder walls and rings are both stronger than the aluminum piston, the piston can be damaged or broken resulting in greater damage and the broken pieces may settle up in the bottom of the crankcase causing more damage, so it’s good to repair a broken rings immediately.
CAUSES OF BAD AND BROKEN RINGS
When an engine gets overheated, the piston will expand, reducing the piston-to-cylinder clearance. This reduced clearance make a metal transfer from the piston to the cylinder wall called galling. This transferred metal can build up on the cylinder wall and make leak or break of the top compression rings. Oil control rings could break if there is excessive piston-to-cylinder gap making too much piston slap to occur. The skirt of the piston, and indeed the cylinder wall can be spoilt and this damage could destroy the oil assembly ring control.
SEE ALSO:HOW TO CHANGE PISTON RINGS