4 Common Factors Contributing to Marine Engine Early Wear

All types of engines and parts get worn out due to continuous usage and working. Proper maintenance and routine checks are necessary to ensure that these engines work for a longer time. Below are some reasons that lead to early wear in marine engines and how it can be minimized:

1. Fuel dilution

2. Low oil pressure

3. Leakage in the air inlet system

4. Dirt in lubricating oil

FUEL DILUTION.

Dilution is a process of reducing the concentration of a solute in a solution, usually by mixing with more solvent.

Checking it mechanically, fuel dilution simply means fuel finding its way into the lubricant and once this happened, the viscosity of the lubricant drops (ie oil become lighter) leading to the following problems:

1. Washing of the sleeve wall. During the engine strokes (piston at TDC & BTC) oil delivered from the spray jet to cool and lubricate the piston in the sleeve would not serve its purpose again because of loss of viscosity.

2. There will be no lubrication to main and connecting rod bearings, leaving both bearings to drive metal to metal.

3. Viscosity becomes lighter causing contact between metal surfaces, which would lead to rapid or early wear of the bearings.

CAUSES OF DILUTION

1. Leaking injector or nozzle

2. Wrongly tightening of fuel line

3. Fuel pump or injection pump mechanical seal failure

4. Crack top cylinder head.

LOW OIL PRESSURE.

The simple step to low oil pressure begins with knowing the oil movement. Oil pumps circulate oil under pressure to an oil regulatory valve, same passes to oil filters then to the oil galleries and to the rotating bearings, pistons, camshaft, etc. Then after much lubrication, the excess returns back to the sump through the oil relief valve. But if the oil relief valve is bad, the oil pressure will remain low if the valve is opened constantly.

CAUSES OF LOW OIL PRESSURE:

Lubricant is a key and a vital point in the life of an engine, therefore much attention is to be given to any engine whenever it is in motion.

When the oil pressure gauge detects low oil pressure, the following are to be checked:

1. Not enough oil in the sump ( check deep stick)

2. Engine wear ( shell bearing)

3. Intermediate bearings wear

4. Bad oil pressure gauge

5. Bad oil pump

6. Bad relief valve

LEAKAGE IN AIR INLET SYSTEM

Air is an essential element for any engine normal working principle. Some engines are designed to be air cooling systems while some are water cooling. Hence, if the expected amount of air required for cooling the engine during working is not admitted, the engine would result in overheating which may lead to engine wear if it is not quickly noticed. Therefore, all air components are to be coupled with its correct gasket and tight to its specification to avoid air leakage that would lead to early wear.

DIRT IN LUBRICATION

Lubrication plays an important role when talking about engines. In fact, an engine can be put on without water for a few seconds but you can't try that without oil. As such, much concentration is needed during engine maintenance or overhauling. All spare parts are to be properly washed and blew with compress air to avoid any foreign particles, especially when bending the crankshaft, power pack installation, mounting of the pump and its accessories, top cylinder head, etc. And once maintenance repair is over, the engine is expected to run at most four-five hours with new oil as required and drain off the oil to flush the system and keep it free from any debris.

We hope this article helps you get more aware of taking proper care of your marine engines and also improve your engine operations.

Do you experience any more problems or know any other marine engine problems which should be added to this list? Let us know how to help you. Call (+234)706 247 6068 or visit www.ugpeotechnique.com.