Loud knocking or metallic noise from engine while running

Safety first: If a new loud knock develops, shut down the generator immediately to prevent catastrophic failure.

• Basic checks: Verify oil level and quality. Low or dirty oil can accelerate wear.
• Flywheel bolts: With engine off, inspect flywheel housing area for loose bolts or damage.
• Injector isolation: On diesel models, a technician can crack injector lines one at a time to identify injector knock versus mechanical knock.
• Do not continue running: Persistent knocking usually indicates serious internal wear. Arrange for professional engine inspection and overhaul.