Standby diesel generators

Steps to ensure yours works when you need it most.

Standby diesel generators
Standby diesel generators

Standby diesel generators

Steps to ensure yours works when you need it most.


Maintenance advice

A planned preventative maintenance regime will reduce your running costs and prolong the life of your engine.

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Standby generators play a very important role providing uninterrupted power in mission-critical operations. You will have thought hard before purchasing yours, investing so you are confident your operation – be it a data centre, healthcare facility or residential tower – will continue smoothly, when your main power grid fails.

That shouldn’t happen often, but if it does, you need to be sure your standby generator will be ready to kick-in flawlessly. There are a few simple steps you can take to keep your standby generator engine in good working order, so that when you need it, it’s there for you.

General servicing and maintenance
  1. Service your genset regularly. If you aren’t using the engine very often, it can be tempting to skip services, but this could cause problems later.
    Changing engine oil and filters is particularly important if your generator is not in a controlled environment. Dust can impact the engine’s operation and condensation can collect in the engine and react with contaminants in used oil.

  2. Maintain the fuel and fuel supply. It is very important to ensure fuel supply remains fresh and condensation is regularly drained from the fuel tank. It’s also important to change the fuel filters as prescribed even if the engine is not being used. Bacterial growth can permeate the fuel system leading to clogged filters which will impact the gensets ability to start when needed.

  3. Regularly check the batteries and starting system are at full charge and ready when needed. Insufficiently charged batteries is one of the leading reasons backup generators don’t start when needed.

  4. Top off the cooling and oil reservoirs to leave less room for condensation to collect and cause corrosion.

  5. Ensure that the start switch is switched back to automatic mode after completing a service. This can avoid a costly no start condition when the genset is needed in an emergency.

  6. Regularly check the condition of the air filters. Remove any dust or blockages that may have accumulated on the air filter covers due to standby periods.

Regular testing
  1. Regularly test the engine, but don’t only run it at no or light load.

a. Testing at no load or light load

Operation at no load or light load should be avoided. If your schedule includes weekly or monthly exercising at no load or light load, the operating period should be kept down to minutes, or until the battery charging rate returns to normal.

On engines with light load profiles, we recommend regular oil sample analysis and corresponding oil changes. This will help detect excessive fuel dilution and general oil deterioration avoiding premature engine component wear.

Contact your local distributor if you experience a failed start/stop event. It’s important to complete a thorough check, particularly, inspecting the exhaust system for unburnt fuel and draining accordingly. This should be followed up with a minimum of four hours operation at full load.

b. Testing at full load

It’s best to set up a regular programme where you run the generator at full load for a minimum of four hours. This will keep the battery in good working order, burn off any build-up of carbon in the engine and exhaust system and allow your team to practise their processes for switching back to prime power after the generator has been in use. Your generator OMM should provide guidance on recommended timescales for your specific machine.

Load should be built up gradually from zero over the first hour and the balance completed at full rated load.