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We Buy & Sell Industrial Generators

Established 1981



History of Diesel Service & Supply (now Generator Source)

Reception Area at Diesel Service & Supply Office
Diesel Service & Supply was established in January of 1981. The size of the first shop was only 1,205 square feet and all operated by one man. Today, we are located on a 14-acre industrial complex with multiple buildings to support increased business capabilities and expanded offerings to provide local generator service and rentals in Colorado and Southern Wyoming. For additional details on Diesel Service and Supply's history, and our transition to Generator Source, see below.

Evolution to Generator Source, LLLP

In March of 2011, Diesel Service & Supply officially became a division of Generator Source, LLLP. The original owner and founder maintains day-to-day operations with total commitment to customer service and satisfaction. We also began expanding offerings to include rental and field service divisions of the business in 2017.

Our primary focus has always been on large industrial and commercial generators with diesel and natural gas fueled engines. We maintain an inventory of generators from 50 kW to 4,000 kW, with top manufacturers such as Cummins, Caterpillar, Kohler, SWP, Generac, and Baldor to name a few. We purchase generators and offer trade-in options to customers upgrading their emergency or standby power system. 

The staff is comprised of experienced professionals, including electricians, riggers, and field technicians, which allows us to offer both in-shop and field services. A sampling of our customers included Sprint, Walmart, Office Depot, CITGO, Haliburton, Clear Channel Communications, and Denver International Airport. Both large and small-sized business are treated with professionalism while we fulfill their power generation needs.

Diesel Service & Supply was one of the world's leading supplier of used and surplus generators. Often these generators have low operating hours because they are used to supply emergency or standby power when utility power fails. All generators must pass a 31-point inspection prior to a sales advertisement. We are a member of the Electrical Generating Systems Association (EGSA), which offers us the latest training to technical force, trade show participation, updates to industry specifications, and continuing education benefits. 

Corporate Progression to Generator Source, LLC

To help further demonstrate our comment to generators and to rebrand with a more memorable name, we officially changed our name from Diesel Service & Supply to Generator Source.  Our web address also changed to On January 15, 2020, Generator Source, LLC became our new operating entity. Through the transition, Generator Source retained generations of experienced staff members. We still offer all of the same services that Diesel Service & Supply provided customers for decades. Below are highlights of the services that we offer:
  • Industrial & Commercial Generator Sales
  • Purchasing / De-installs & Decommissioning
  • Shipping & Receiving
  • Customized Shop Services
  • Generator Rental Throughout Colorado
  • Field Service in Colorado & Southern Wyoming
Yard Crane & Fork Truck Loading 4000 kW Generator

Sales/Purchase/Shipping & Rental 

Fourteen acres of storage area with multiple buildings allow us to stock a large variety of generators. Matching the client with the correct generator is our primary concern. Once the correct generator is purchased, our after-sales services stand second to none.

New, Surplus & Used Generator Sales

Standby, prime, and continuous are ratings for generator operating time and load. Outdoor, indoor, and portable generator sets are common manufactured styles.

Shipping Generator & Heavy Equipment

Once the generator is purchased, we arrange for shipping. Our approved shippers must meet our stringent requirements and be experienced at moving heavy equipment. Our in-yard crane handles most generators that are inbound or outbound. Once a generator arrives on a customer site, we arrange for a local crane service for unloading or loading operations.

Rental Generators

Our inventory includes a large stock of rental generators. Portable generators are a popular option for short-term projects. Renting a generator relieves the operator from maintenance and repair tasks. All rental units are maintained to the manufacturer's specifications and are ready for connection to the load. Lease to purchase options are available.

Shop Services

Load Testing Indoor Cummins GeneratorOur 10,000 sq. ft customization and fabrication shop allows us to complete all types of generator projects. Technicians are equipped with the most updated tools to troubleshoot and repair any generator issue. A variety of load bank testers are available to fulfill most any generator testing requirements. Yard equipment includes various fork trucks and cranes to move and load generators. When a pre-owned generator arrives, a 31-point inspection is performed. Once the generator has passed the inspection, it is ready for sales. Customers often require customizations such as load bank installations and operating in adverse climate customizations. Extreme weather (hot, cold, or wet) and dusty operating conditions are common modifications. Customer-defined needs inspire modifications.

Field Service

In-depth shop service capabilities made the transfer into field service offerings the next step in company growth. Generator Source is responsible and accountable for the service side. Maintenance is the main priority with generators. Buildings with critical power supply requirements are required and monitored by both State and Federal Agencies. 

Hospitals, airports, data centers, and industry that have processes that cannot have power interruptions are among the buildings that fall under the critical power rating. Generator load testing is a required part of their maintenance program. This test is completed after the manufacturer's required maintenance tasks are performed. Maintenance contracts are geared to the needs of a customer. A standby generator can be utilized while the primary generator is load tested.

Maintenance to all generators in every application extends operational life and dependability. Sometimes, generators fail to supply power when the utility power fails. Often, this arises on a building acquisition that has an installed generator that has been sitting idle for a long period of time. Troubleshooting and repair skills possessed by our technicians allow them to diagnose the problem and replace the correct part the first time out, saving dollars in parts and labor. After repairs, the generator can have maintenance tasks that were not completed, performed.

Decommissioning/Commissioning & Deinstallation/Installation

Field Service Truck
To decommission is to take out of service. To commission is to place into service. Projects where the building is slated for demolition use decommissioning and deinstallation services only. Deinstallation is the process of removing the generator and associated supporting equipment. Commissioning and installing steps are performed in system upgrades. We commonly remove existing generators and replace them with a model that has more capabilities.

We have the diversity to handle any project head-on. Location and accessibility dictate the equipment and tools needed to perform a job. If the location has a generator, we can maintain, test, repair, or replace it with an upgraded model. Nationwide service is offered, and we accept most any job. Recently, we upgraded a locomotive generator with one that had a greater capacity. This required fabrication services for the installation.


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