1. Make sure every record belongs to the same unit
Keep a single folder for the proposed unit. Label each document with its date and source so an older report does not get mistaken for a current inspection.
- Collect clear generator and engine nameplate photos, including model and serial number.
- Compare output, voltage, phase, frequency, fuel, and operating duty with the project requirements.
- Ask the seller to identify the serial number on records and test reports; resolve mismatches before proceeding.
2. Build a condition file
Request hours, prior application, service records, known defects, photographs, and available fluid-analysis and load-test reports. Caterpillar’s used-equipment buying discussion recommends reviewing records and offers inspection or witnessed testing as ways to evaluate a specific unit. See the manufacturer reference below.
- Ask what has changed since the last inspection or test.
- Record missing components, disclosed faults, and any unresolved alarms.
- Separate work already completed from repairs the seller only proposes to perform.
3. Ask what ‘load tested’ actually means
Request the report instead of relying on that phrase in a listing. For a buyer’s document review, ask the testing party to identify the unit, date, procedure, applied load, duration, readings, findings, and any corrective work. This is a procurement checklist, not a test procedure or a certification standard.
- Does the report identify the offered generator?
- Does it state the test conditions and what was measured?
- Are faults or interrupted tests documented?
- Was any subsequent repair followed by additional testing?
- Does your project require further inspection or witnessed testing before acceptance?
4. Define what you are buying and how it leaves the site
Have qualified personnel handle inspection, electrical disconnection, testing, and lifting. Do not energize or open equipment just to complete an inquiry.
| Before committing | Question to resolve |
|---|---|
| Included equipment | Which tank, enclosure, controls, transfer equipment, and loose accessories transfer with the unit? |
| Acceptance | Who inspects it, what is acceptable, and what happens if a problem is found? |
| Warranty | Who provides it, what is covered, and what is excluded? |
| Removal | Who disconnects, rigs, loads, transports, and unloads it—and by what date? |
| Payment | Who is selling the unit and what are the written payment milestones? |
Common questions
Should I buy a generator based only on low hours?
No. Review the history, current condition, available records, and inspection terms together. A low hour-meter reading is not a substitute for a condition assessment.
Does a previous test guarantee that a used generator is ready for my site?
No. Review what the test covered and confirm the unit’s suitability for your project. Site integration, transfer equipment, commissioning, and acceptance requirements remain separate questions.
Manufacturer references
References explain general concepts. Confirm the documentation for the specific equipment and project.