Important Points in Second Hand Generator

Key Points of Purchasing a Second Hand Generator

Purchasing a second hand, underutilised generator provides many advantages. The lowest cost way to get a high quality generator is to buy a second hand generator; For this reason, companies have a second-hand sales unit. However, there are many points that should be considered before making the purchase, which constitute the main purpose of this article: The first consideration is choosing a generator that is powerful enough to meet your specific power requirement. For more detailed information on this subject, you can review our article on determining the size of the generator. Once you’ve determined the power you need, it’s time to examine other factors.

Here are some key considerations when purchasing a used generator (diesel, natural gas, electric propane, gas, etc.):

  • Age, Working hours and Usage
  • Manufacturer History and Brand Reputation
  • Maintenance
  • Physical Wear and Tear
  • Performance in Load Test.
  • Purchase (Broker or Distributor)

Generator Age, Working hours and Usage:

The first thing to consider when buying a reliable second-hand generator is; are the operating hours, age and history of the generator set. First, check how long it has been working. It may also be helpful to know what it is used for (prime/standby). Generator used as standby or backup energy source; It is more well-maintained and less worn than the generator used as a prime or continuous energy source. However, do not forget about the cases where the age and usage information of the device is not available. Dealers often do not have detailed information about where the generators they obtained from foreclosures and auctions come from and for what purpose they are used. In such cases, the reputation and technical expertise of the seller is important.

Manufacturer History and Reputation:

While the brand and model are not always critical, the generator manufacturer’s history and reputation play an important role in the used machine you choose. Do not rely on unknown brands as you will buy a device that you can trust to meet your electrical energy (prime or standby). By choosing a reliable manufacturer, you can get a quality device as well as an advantage in terms of spare parts and warranty.


You may not be able to obtain detailed information about the maintenance of the generator in the past; However; You can check the knowledge on maintenance, diesel engine repair, power units and transfer boards of the company you purchased. You can query the vendor’s current knowledge by asking simple questions about the procedures they use.

Physical Tear and Wear:

  • Visual Inspection:
    The next step must be a visual inspection. A generator, like any mechanical device, may contain wear during operation. Check all mechanical components for wear or malfunction. Check the mechanical parts for any cracks or corrosion. If any suspicious part is detected, it should be replaced with parts recommended by the manufacturer.
  • Bearing and Shaft Bearing Replacement:
    All bearings and shaft bearings must be replaced in any condition, unless they have been replaced by the dealer. The replacement process prevents any damage these parts can cause while the generator is running. Bearings and Shaft bearings are under pressure during generator operation and it is very difficult to test these parts for any pressure they encounter while the generator is running. Therefore, from the point of view of safety, it is optimal to replace these parts. The same is true for bolts and studs.
  • Wiring and Solder Integrity Check:
    Check the strength of the solder parts. Also check the integrity of electrical components and coils. Test the cable insulations in case of any malfunction.
  • Load Test:
    The load test is the most important standard test the seller should have done, inquire again to be sure. A load test helps to determine the overall efficiency in electrical power generation. The generator’s good response to variable loads is often an indication of its efficiency at specified load limits. The type of electrical power produced by the generator indicates the general condition of the generator set. The test should check the appropriate output and frequency. The test should be repeated three times to eliminate unexpected power failures.
  • Purchhasing (Broker or Dealer/Distributor):
    Industrial diesel generators are complex, fine-tuned machines that must be tested by certified technicians to operate correctly with optimum efficiency when you need them most. Since most diesel generators are high priced, the reliability of the purchaser is important. Therefore, in order to eliminate risks, companies that have gained a certain industrial experience by providing years of service in this field should be preferred.