mantenimiento grupo electrógeno

How to do the maintenance of a Generating Set

The diesel generating set is a reliable and easy-to-use system for generating electricity. As a user, you have to keep it efficient and controlled, just as you do with your car when you take it to annual maintenance reviews.

How to do the maintenance of a Generating Set?

The maintenance of a diesel generator

mantenimiento grupo electrógeno

No matter how expert you are, if you have a generating set you probably want to limit the effects of power cuts of the utility. However, it can happen that when the network supply fails, the genset does not start and does not fulfill its function. Unfortunately, we forget to run it, keep it clean, and maintain it. Just figure out what would happen if you left your motorbike stopped for several years in the basement and suddenly you were to start it. Do you think it would start at the first attempt?

The generating set needs maintenance, both the diesel engine and the other components require periodic care and scheduled tests.

For the first, the most important thing is the replacement of lube oil and filters, while the alternator and the electrical panel need an check and a periodic cleaning of the terminals. If the generating set is installed in a canopy, you should check regularly the status of the moving parts such as hinges, fasteners and paint. Perform these basic operations at least once a year.

It is also recommendable to start up the genset each week or at least once a month.

The maintenance plan for a generating set

I give you below a complete maintenance plan you can use as a guide when performing the services of your generating set.

Preventive maintenance is the most important to ensure that your equipment remains in optimal conditions.

The operations you must take into account, ranging from an inspection of the overall conditions, to an in-depth control of the lubrication system, the cooling system, the fuel system and the electrical part including the batteries and the speed regulator

Speaking of an emergency generator, it is advisable to check the general condition frequently; this is to ensure that there are no damages, loosen parts or that dirt has accumulated.

You can control the appearance of your generating set every week, check that the preheating resistance is hot and take a look at the coolant, oil and fuel levels. You will ensure that there are no leakages, for example, through a damaged gasket. I also recommend that you start up the generator frequently to make sure that the batteries and charger are in good condition. The oil level must be checked with the engine off using  the dipstick installed on the side.

For the cooling system, remove the lid -always with a cold engine– and if necessary add coolant as far as indicated by the filling mark or up to about ten centimeters below the level of the lid. Use a mixture of water and glycol 50/50 unless the manufacturer tells you otherwise.

Check if the radiator has holes, damages or losses. Clean the surface with air or water, and be careful to touch the radiant panel fins, they cut! Touch the preheating resistor and check that it heats correctly throughout the circuit and that there are no obstructions.

While the generating set is running, check the oil pressure – approximately 4 … 5 bar – and the coolant temperatures -about 70 … 80ºC-, if you detect something anomalous, it is probably the warning of a future problem. Analyze the cause and solution before it causes damages. Pay attention to the noise of the engine and its appearance; observe if there are many vibrations or excessive smoke in the exhaust. Check if any alarm is present in the controller display.

Now, with the generating set in operation, check the fuel hoses, both the supply and the return hoses. The pipes must be loosen and away from other components that can damage them. Help yourself with strips and brackets to anchor and route them correctly. Check that the filters are secure and that there are no leaks. If you detect any cracks, replace the defective component.

Sometimes a glance is enough to detect an anomaly!

Check every month the mechanical parts such as the tension of the fan belt, the fixing of the exhaust silencer and the engine and alternator supports. Clean the dust from electrical parts. Check the battery and terminals, the connections should be clean and tight, If you see traces of rust or acid, replace the connectors and clean the area. Check if the battery has been damaged by releasing acid.  With the new gel batteries you should not worry much, just make sure that the connections and the chassis are not damaged. In any case, check the type of battery and read manufacturer instructions for more care.

At least change the oil once a year or every 500 hours of work. A synthetic oil 15W40 should be suitable, although I advise you to find out what the manufacturer recommends. Replace the fuel, oil and intake air filters and empties the accumulations of water in the tank. Finally, clean the radiator and the breather from the crankcase. After changing the oil and fuel filters, take them to a waste center, do not treat them as conventional garbage as they are very polluting and need special treatment.


I recommend adapting the maintenance plan of your generating set to the manufacturer’s recommendations and the environment where it is installed. If you have it in a dusty environment, clean the air filters and radiator more regularly. If the fuel you get is of poor quality or if there is a lot of water condensation in the tank, clean the diesel filters more often and drain the condensation.

You can also add a diesel filter with water separator to make sure the engine does not get damaged.

When your machine is not in emergency, but works many hours a day and perhaps in extreme working conditions or exposed to the weather or dusty environments, I recommend checking with the manufacturer or a specialized company so you can make a custom maintenance schedule. Additionally, you must ask for a record of all the operations and the proof of the parts that they replace.

To learn more

Here a very useful video that gives practical information on what to do with a portable generator. Maintenance on

Do not underestimate the danger of leaving dirt in the electrical panel because they can cause electric arcs.

To learn about maintenance-free batteries, check out

Photo Credit Chris Christian