What causes thick sludge at the oil filler port?
2 Answers
Sludge is a residue left behind by prolonged use of mineral oil, especially in engines with oil additives, which are more prone to sludge buildup. If the sludge is excessively thick and you wish to avoid disassembling the engine, you can remove the valve cover and oil pan, soak them in diesel, and then scrub with gasoline. Below are detailed explanations: 1. Causes: Adopting the bad driving habit of "high gear at low speed." Prolonged idling and low-speed driving. Using gasoline with inadequate purity and quality. 2. Effects: Difficulty in cold starts, failure to reach the specified idle speed when cold, and in severe cases, stalling during cold idle. Low idle speed after the engine warms up. Reduced engine power, sluggish acceleration, and increased fuel consumption. Deterioration in engine exhaust emissions, which also shortens the lifespan of spark plugs, oxygen sensors, and catalytic converters. Carbon deposits can cause the piston rings to stick, affecting their sealing performance, leading to increased oil consumption, engine oil burning, and a shortened engine lifespan.
I noticed a thick layer of sludge around the engine oil filler cap, which usually happens when oil changes are neglected for a long time. Having driven for ten years, I've encountered similar situations caused by aged and deteriorated oil accumulating dust and impurities. Frequent short-distance driving makes it easier for water vapor and combustion residues to mix and condense into a sticky substance. It's recommended to change the oil every 5,000 kilometers, using full synthetic oil for better high-temperature resistance, while also checking if the engine seals are leaking. Ignoring this can clog the pipes, affect heat dissipation, increase engine wear, and raise fuel consumption. Last time I overlooked it and ended up spending nearly a thousand on a replacement part—totally not worth it. Regular maintenance is the real money-saver; don't wait until problems become severe to address them.
