New Cummins Diesel Generator Sets Causes of Blue Smoke from

Causes of Blue Smoke from New Cummins Diesel Generator Sets

The occurrence of blue smoke from a brand-new Cummins diesel generator set is typically caused by improper operation or maintenance practices. New diesel generators must undergo a 60-hour break-in period before handling full loads, following the operating instructions strictly during this phase.

After initial operation, the engine oil accumulates metal shavings and particles from component wear. If not removed promptly, these contaminants can:

Impair lubrication of moving parts.

Scratch cylinder walls if trapped between piston rings, leading to cylinder scoring.

Allow oil leakage into the combustion chamber, causing blue smoke (oil burning)

Solutions & Preventive Measure

1. Oil Replacement After Break-In

Drain and replace the oil within the first 60 operating hours.
Alternatively, filter and reuse the oil after sedimentation.

2.Pre-Start Manual Cranking

Rotate the flywheel 2+ full turns with a screwdriver before starting (more in cold weather).
Ensures oil circulation to critical components.

3.Proper Warm-Up Procedure

Run the generator at low speed for 5 minutes after startup.
Allows lubrication and preheating; check oil pressure immediately—shut down if absent.

4. Diagnosing Severe Oil Burning

Use the cylinder cut-off method: Disconnect fuel supply to each cylinder one by one.
If blue smoke stops when a specific cylinder is cut off, inspect its piston rings and liner for damage.
Replace severely worn parts.