Generator starts but immediately stalls when load is applied

Safety first: Ensure critical loads are protected by alternative supply if possible. Open the generator output breaker before testing.

• Run no-load test: Start the generator with the breaker open. If it runs smoothly without load, the issue is likely load-related.
• Gradually apply load: Close the breaker and add load in stages, monitoring engine response and frequency. Identify the load level at which stalling occurs.
• Check for overload: Compare kW/kVA at stalling point with the generator rating. If above rating, reduce connected load or reconfigure the installation.
• Inspect fuel system: Under load, a partially blocked filter or weak lift pump may starve the engine. Replace filters and check fuel supply as needed.
• Governor/turbo check: If the engine smokes heavily and lacks power, the turbocharger or governor may be faulty; professional service is recommended.