Diesel engines can go for long periods of time without major repairs. Since a diesel engine does not have an ignition system, certain normal gasoline engine maintenance like replacing ignition wires, spark plugs, distributor caps or rotors is not required. There is no need for ignition tune-ups either.
However for smooth functioning diesel engines do require the following regular maintenance
1. Changing the lubricating oil
This is usually necessary on a more frequent basis than gasoline engines - generally every 3000 miles
2. Changing the air filter
Since diesel engines experience high intake pressures, the air filtering system is important to not only filter media but also to cool the air.
3. Changing the oil filter
While a gasoline engine may give less mileage or performance with a dirty fuel filter, this can be more serious in the case of a diesel engine where dirty fuel can damage a diesel engine's fuel injection system. The filter should meet or exceed the standards suggested by manufacturer so that sulphur and carbon residue are removed. Synthetic oil is also recommended.
4. Early warning system
The early warning system that warns of engine overheating should be checked for functionality. A gasoline engine if overheated can be shut off, cooled down and restarted. However if a diesel engine gets overheated, it will be damaged.
5. Changing the fuel filter
It is important the change the fuel filter as recommended by the manufacturer in order to prevent condensation from building up and getting into the fuel injectors. The fuel tank should also be kept full to avoid moisture forming.
6. Checking Gaskets
Gaskets should be checked and replaced on all critical areas especially in the combustion mounting areas and coolant hoses.
7. Bleeding the fuel system
While some diesel engines have self bleeding systems, others which do not, need to have the fuel system bled to get a steady air free flow of fuel. This becomes necessary after any of the following situations have occured
- Running out of fuel.
- If fuel shut off valve is left closed and engine runs out of fuel.
- Replacing fuel filter.
- Fuel injector nozzle or injector pump repair.
- After repairing or replacing any fuel line.
- Before putting engine back into service in the spring, if fuel system has been drained.
- Replacement of electric or mechanical fuel pump.
- Any time air is permitted to enter the fuel system.
8. Draining the water separators
Since diesel fuel absorbs water more than gasoline, it can get contaminated very easily. Therefoer most diesel engine vehicles have a water separator that collects water from fuel. This water needs to be drained regularly from the separator using a drain valve called a petcock. Some water separators are self-draining.
9. Glow plugs
Glow plugs enable a diesel engine to get heated for combustion to take place. After prolonged use, these can wear out and may need to be replaced.
10. Installing an engine heating kit
Engine heating kits for diesel engines are especially useful in winter when diesel engines are hard to start. This saves fuel and prolongs the life of the diesel engine while cutting down on exhaust emissions. It also eliminates the need for idling which cause wear and tear on the internal parts of a diesel engine not to mention unnecessary fuel consumption.