What are the consequences of running a four-stroke engine with poor fuel injection atomization?

Running a 4-stroke engine on Heavy Fuel Oil (HFO) with poor atomization can lead to various mechanical and performance issues. Poor atomization means the fuel isn't broken into fine droplets as it should, affecting the combustion.

Possible critical outcomes and what can go wrong:

Combustion Issues

• Incomplete combustion causing large fuel droplets don't burn completely, leading to carbon deposits and unburnt fuel in the exhaust.

• Delayed ignition causing poor atomization slows down the mixing of fuel and air, increasing ignition delay.

• Knocking or detonation causing delayed combustion can cause knocking, which is damaging over time.

Engine Component Damages

• Carbon deposits causing build-up on injector tips, piston crowns, valves, and cylinder heads. This reduces efficiency and increases maintenance needs.

• Exhaust valve burning caused by incomplete combustion can overheat and damage exhaust valves.

• Piston ring sticking or wear causing carbon deposits that can cause rings to stick, reducing sealing and increasing blow-by.

• Turbocharger fouling causing unburnt fuel and soot can clog the turbocharger, reducing performance.

Lubrication Issues

• Oil contamination as unburnt fuel can mix with lubricating oil, reducing its effectiveness, and accelerating wear.

• Increased acid formation as poor combustion can lead to higher levels of sulfuric acid, especially with HFO, which has high sulfur content. This further accelerates liner and bearing wear.

Temperature Problems

• Hot spots and overheating as uneven combustion can create local hot spots, stressing metal components.

• Poor heat distribution can cause thermal stress, leading to cracks or warping in cylinder heads or liners.

Performance and Efficiency Loss

• Reduced power output as poor combustion means less energy is extracted from the fuel.

• Higher fuel consumption as more fuel is required for the same power output.

• Increased emissions as Incomplete combustion leads to higher levels of soot, CO, and unburnt hydrocarbons.

Long-Term Consequences / Risk Assessment

Running a four-stroke engine with poor fuel injection atomization can increase maintenance intervals and costs, shorten engine life and in worst case result in higher risk of catastrophic engine failure if not addressed