The standard is how much?
If the manual states that normal oil consumption in tough conditions reaches 600 g per 1000 km or more, that claim should raise questions about transparency. Such figures represent a heavy cost for a serviceable engine and hint that design flaws may be swept under the rug to protect warranty coverage. Honest oil burning numbers should not be taken as the norm.
In a well-functioning engine, zero oil use is unlikely, but excessive consumption is equally problematic. Lubrication should stay on the cylinder surface as the piston moves; otherwise the upper piston ring can run dry, leading to sticking and chatter. If oil particles remain during the working stroke, they should burn off. Realistically, an engine that uses oil cleanly should show far less consumption, typically well below 50–100 g per 1000 km, under normal operation.
Oil burning can often go undetected. Some owners start by adding small amounts of oil, only to see consumption creep higher and higher between changes. If not monitored, the habit can escalate to needing gallons between service intervals. It is prudent to address potential oil burning early rather than letting it fester.
At times the root cause lies with the operator rather than the manufacturer. Overloading the vehicle can stress an engine, and cold starts on steep climbs strap the piston rings with extra load, sometimes triggering oil burn.
1. Check ventilation
The crankcase ventilation system creates a slight vacuum under the piston, while gases escaping from the combustion chamber can raise pressure there. Those gases need to be cleaned of the smallest oil droplets and routed to the intake tract so they enter the cylinders and burn off safely.
It is essential to inspect and clean the oil separator and the valve that limits crankcase vacuum. If it freezes, the intake system may draw oil from the engine while the system itself becomes contaminated, causing the throttle body to accumulate oil.
2. Clean the nozzles
If injectors fail to spray fuel properly, combustion becomes inefficient and deposits form on the cylinder walls. That dilutes the engine oil, increasing volatility and allowing oil to travel into the crankcase ventilation pathway, then slipping into the upper piston space and burning there.
Therefore, inspect nozzle spray quality and clean them as needed. Direct-injection engine injectors, which can be stubborn to disassemble, can often be cleaned with detergent additives in the fuel. A fuel fill with enhanced cleansing properties can help maintain injector and energy system cleanliness.
3. Use high octane fuel
Fuel choice is a frequent debate. To minimize oil burn, it helps to use a fuel with a higher octane rating. Running on low-octane gasoline tends to raise engine temperatures and promote piston-ring coking, enabling oil to enter the combustion chamber.
When the Largus editors with a K4M engine used high-octane fuel, they reported no signs of oil burning after 140,000 km, suggesting benefit from better fuel quality even in older engines.
4. Monitor the temperature
Modern engines run hot, with operating temperatures often reaching 115 C or higher. Even premium heat-resistant oils approach their limits. A slight excess can cause coke buildup in piston grooves, reducing ring mobility.
The most common overheating culprit is a dirty radiator for the engine and air conditioning. Regular washing helps, as does ensuring airflow remains unobstructed. Fine-mesh nets designed to block insects and pebbles should be removed or replaced with a larger mesh. Additional heat can come from aggressive protective devices that reduce clearance in the engine bay.
For cars without a temperature gauge, use trip data, or pair an ELM 327 scanner with a smartphone app that shows exact temperatures for vigilance.
5. Change the oil by operating hours, not just mileage
Oil burn is tied to operating conditions. Traffic jams versus highway driving create different stress levels for the engine. Some engines may show higher oil usage on trips of 100,000 km, while others remain stable.
Oil consumption is often not obvious immediately after an oil change; it may become noticeable after 5,000–7,000 km as additives wear out and burning begins. If the oil is poor or the work conditions are hard, adjusting the change interval to engine hours (about 300 hours) or considering average speed may be wiser. If average speed sits around 20–25 km/h, changing oil every 7,500 km is reasonable.
6. Consider a more viscous oil
Using a thicker oil with higher temperature viscosity (for example 40 or 50) is generally only suitable for older engines. Modern engines with tightly toleranced channels can suffer from oil starvation with overly thick oil, so follow the manufacturer’s viscosity guidelines when deciding on oil selection.
7. Decarbonization as a last resort
Decarbonization is often the final step before disassembly. On a warm engine, removing plugs and applying foaming decoking agents to the cylinders can help. After a short rest, dirty liquid is drained, and the walls receive lubrication to keep surfaces even after cleaning. Decoking fluid can be mixed with oil to reach piston surfaces and wash the oil scraper rings, then drained after ten minutes of idle time. A flushing oil completes the process, followed by a proper oil fill and careful monitoring for oil burn recurrence.
Foam-based decarbonization is preferred for its broader cleaning action within the combustion chamber. The author suggests applying these tips, with the possible exception of the decarbonization step, as preventive measures even if the engine currently shows no signs of burning. The aim is to prevent maslozhor from appearing at all.
- The American Cyclo automotive chemicals and SUPROTEC additives help keep vehicle components and assemblies in good condition.
- Consult the reference books from the publishing house Behind the Wheel for maintenance guidance.
- Behind the Wheel is also available on VKontakte.
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