Why sludge appears in the oil shell

Release time:

25 Jun,2024

Sludge is the fuel residue in the engine. Also known as carbon mud, it remains in the engine oil and is filtered by the oil filter. However, if the oil or oil filter is not replaced, sludge will accumulate and the oil will become dirty and deteriorate. If the oil is black, it is probably caused by sludge, so the oil needs to be changed.

First of all, is this sludge normal? It should be abnormal. Many people also explained that this kind of oil smell is normal and every engine will have it. This statement is wrong. The oil is pumped to all parts of the engine by the oil pump through the filter screen, and then returns to the oil filter element from top to bottom. The impurities are filtered and flow to the oil pan. This sludge can be said to be several times the viscosity of oil, basically has no fluid performance, and will be firmly adsorbed on the surface of the oil pump filter. The filter cannot effectively absorb enough oil, which will affect the circulation performance of the oil, accelerate the deterioration of the oil, and increase the amount of sludge. Engine oil has a cooling effect in the engine, and insufficient flow leads to excessive local temperature of the oil, which is the root cause of sludge.

When the oil circulates, the oil filter will leave a residue in the filter. If the oil circulation is normal, the sludge should be in the oil filter element, not adsorbed on the surface of the oil pump filter screen. Turbocharged engines can use low-viscosity oil, but for ordinary engines, change the correct type of oil, sludge is not caused by oil problems. Of course, fake oil is another matter.

Key words:

Longman