Analysis of Smoke Emission Causes in Diesel Generator Sets
Smoke emission from the exhaust pipe of a diesel generator set is generally considered an abnormal phenomenon. Smoke production during diesel engine operation often signals the need to assess whether certain components require replacement or if the entire unit needs maintenance and repair.
The causes of smoke emission during operation can be considered from the following aspects.
1. Causes of white smoke emission in diesel generator sets:
① Engine running too cold;
② Water contamination in fuel;
③ Blown cylinder head gasket or loose cylinder head bolts;
④ Cylinder cracks or water leakage from wet cylinder liner gaskets;
⑤ Other causes leading to coolant ingress into cylinders.
2. Causes of Blue Smoke from Diesel Engines:
① Worn, seized, broken, or insufficiently resilient piston rings;
② Poor oil ring scraping, misaligned oil ring gaps, or incorrect installation;
③ Excessive clearance between piston and cylinder;
④ Excessively high oil level in the oil pan;
⑤ Premature injection timing;
⑥ Other causes leading to lubricating oil entering the cylinder.
3. Causes of black smoke emission in diesel engines:
① Excessive load;
② Poor fuel atomization, low injection pressure, or dripping fuel;
③ Injection timing too late;
④ Clogged air filter;
⑤ Excessive adjustment of the fuel injection pump plunger rod or connecting rod stroke;
⑥ Loose fuel injection pump ring gear locking screw causing fuel quantity imbalance;
⑦ Valve leakage resulting in insufficient cylinder compression;
⑧ Failed intake valve opening in a specific cylinder causing fuel injection without air intake;
⑨ Diesel fuel quality failing to meet specifications.