Generator Servicing & Maintenance Tips

Generator Servicing & Maintenance Tips

7 minute read

Generators, like most products with a working engine and moving components, will always require a certain degree of maintenance and regular servicing to help optimise performance.

There are many different types of generators, from petrol to LPG and diesel-powered, and they come in many forms with varying applications. These include a wide range from portable generators, to standby generators, inverter generators through to industrial prime power generators - all of which will require key maintenance and servicing.

Within industrial, home, office or business environments, it is commonplace to have a backup plan in place to ensure power 24/7. Many businesses in areas such as construction, mining, gas or even within the healthcare industry will rely on a backup power source. Carrying out regular service and maintenance on your generator should also be of paramount importance.

In some cases where industries rely on prime power, such as the health industry, it is advisable that you have a local generator specialist carry out these regular servicing intervals. That said, this blog aims to highlight the key aspects for maintaining your generator and our step-by-step guide will instil confidence that your generator will deliver optimum performance year after year.

Just like your vehicle, for instance, your generator also has key features that you need to stay on top of to ensure the performance remains as it should year after year. This will help to ensure your generator delivers power when you need it the most.

Hopefully you wouldn’t let your vehicle go longer than a year without performing certain maintenance essentials, these can be things such as changing filters regularly, replacing spark plugs and leads, topping up fluids regularly and tyre checks. The same can be said of this when it comes to your generator. The frequency of your servicing will depend on the application of your generator and the hours of work you are putting on the generator.

An annual service in the industry terms is the absolute minimum requirement. But as previously mentioned this can be dependent on the application of the generator and it’s frequency of use.

For the most part, we recommend a regular six month service will help ensure you are staying on top of the essential components of your generator

We always recommend you refer to your manufacturer's user manual provided at the point of purchase, this will be full of helpful tips and advice on the servicing intervals and maintenance of your generator specific to its model.

Simple maintenance and basic checks will save you time and money while also ensuring you will continue to get maximum performance from your generator. All work should be carried out by a competent person. If you are unsure on any of this please contact your local dealer/manufacturer you have purchased the generator from. Hyundai Power Equipment has a full after sales and technical support team available Monday-Friday 8:30am until 5:00pm should you have any questions or need support carrying out your generator service.


It is important that you carry out essential checks on your generator everyday. If your business relies on your generator to function, you need to stay on top of these daily checks:

  • Checking and refilling the fuel.
  • Checking and refilling the engine oil.
  • Check for oil leaks.
  • Check and tighten fastening parts.

Also check your generators general appearance. Check around the canopy for any dents scuffs or notable changes that could cause damage to internal components. This should be part of your daily generator routine check.

Hyundai Power Equipment has become a major player in the generator market over the years. Specialising in a range of generators across multiple applications, from the leisure industry with their inverter generators through to the diesel standby power range with their DHY6000 and 8000 units right the way through to their 1500 rpm diesel specialist units.

Due to this, the team over at Hyundai are best equipped to pass on their knowledge of looking after your generator and the servicing intervals required. They have kindly created a step-by-step guide below by generator type for you to follow. Following this guide and using your user manual these steps will ensure you are getting the optimum performance from your generator year after year.


  • Change engine oil after the first 20 hours then every 100 hours.
  • Replace spark plug every 250 hours.
  • Clean or replace the air filter every 250 hours.
  • Adjust valve clearance every 500 hours.
  • Use SAE30 or SAE15w40 engine oil.


  • Change engine oil and clean oil filter after the first 20 hours then every 100 hours.
  • Replace air filter and fuel filter every 250 hours.
  • Adjust valve clearance every 500 hours.
  • Use SAE15w40 engine oil.


  • Change engine oil every 250 hours, or if using fully synthetic oil, every 500 hours.
  • Clean or replace the air filter every 500 hours.
  • Change diesel filter every 500 hours.
  • Run at 70% load if required every service.
  • Use SAE15w40 engine oil.


  • Change engine oil after the first 20 hours then every 100 hours.
  • Replace spark plug every 250 hours.
  • Clean or replace the air filter every 250 hours.
  • Adjust valve clearance every 500 hours.
  • Use SAE30 or SAE15w40 engine oil.


In order to maintain a healthy generator it’s important that you follow the correct schedule as highlighted in your user manual.

Hyundai Power Equipment have also got you covered with their diesel service kit packages. Available on a next day service over the phone with their onsite parts team or if you prefer from the Hyundai Power Equipment website (link below). We would strongly recommend purchasing your service kit alongside your generator to ensure you have everything ready for that first service. 



If the engine can’t breathe or ignite the fuel properly then the generator will be difficult to start and very inefficient.

If the spark plug looks OK then clean the electrode with a soft wire brush and checking the plug gap is all it should require. If the plug hows any sign of wear or damage then replace it.

The same goes for the air filter, a simple clean is usually all that is required either by blowing dust and debris out if it’s gauze filter or a clean and re-oil if a foam style filter.

It is always better to replace the air filter at the correct service interval rather than clean it.


If the generator has a battery make sure it is fully charged before storing. A better solution is to invest in a trickle charger to keep the battery topped up and ready when you need it ensuring a healthy battery life.

Available Here:

Store the battery in a cool dry place to keep it in good condition and clean the terminals to ensure you always get a good contact.


If your generator is being stored for more than 30 days we would advise you drain all fuel from the tank and carburettor. Stale fuel can cause major issues when trying to start your generator, so while this tip seems pretty straight forward it can help avoid headaches down the line when you need your generator most. The parts team over at Hyundai Power Equipment also have Briggs and Stratton fuel stabilisers available on a next day service to prevent stale fuel and help help avoid this happening to your machine.

TOP TIP: Do remember if you are disposing of any fuel to please contact your local authorities and explain. They will have helpful advice and will guide you on the correct method of doing this.

We hope you have found this to be a helpful guide for you to follow your generator servicing and maintenance schedule. If you have any generator enquiries and would like to speak to the Hyundai team directly please call 01646 687880. The knowledgeable sales team will be on hand to offer you advice to ensure you are getting the correct generator for your application.

If you want to know more about the servicing intervals or are unsure about any of the steps specific to your machine please do get in contact with the Hyundai after sales and technical support team who will be able to guide you through any technical or servicing enquiries you may have.

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