Diesel Engine Lubricating Oil Pressure Issues

When the lubricating oil pressure of a diesel engine is absent or too low, the oil cannot reach the friction surfaces. Conversely, excessively high oil pressure can damage oil seal devices, causing oil leakage; in some cases, it may even rupture or dislodge the oil filter, leading to massive oil loss.

A diesel engine may show no oil pressure at any speed due to three main causes:

1.Blockage of the main oil gallery inlet or the oil passage before the pressure gauge, preventing oil flow.

2.Malfunction of the oil pump, resulting in no oil pumping.

3.Damage to the oil pressure gauge.

Case 1: A diesel engine showed a "0" reading on the oil pressure gauge at low speed. When the gauge connector was loosened for inspection, oil still oozed out. Further inspection by removing the gear chamber cover revealed that the three M8×16 mm bolts on the oil pump cover had loosened partially, causing oil leakage from the pump cover at idle speed. After tightening these bolts, the oil pressure returned to normal.

Case 2: A diesel engine that had undergone medium repairs initially showed normal oil pressure after startup, but the pressure gradually decreased during operation. As the engine speed increased, the pressure dropped further, eventually reaching "0" at high speed. Detailed inspection by Dingbo Power (generator manufacturer) identified the cause: during repairs, old cloth and cotton yarn were used to clean the oil pan and engine inner walls, leaving cotton lint accumulated in the oil pan. At low engine speeds, the oil pump’s suction was weak, so the lint only partially blocked the filter screen, allowing some oil to enter the oil passage and maintain relatively normal pressure. However, at higher speeds, increased pump suction caused the lint to block most or all of the screen, restricting oil flow to the filter (or blocking it entirely), resulting in low or zero pressure on the gauge.

Since 1982, Dingbo Generator has been a generator set manufacturer qualified by the "National Internal Combustion Engine Quality Supervision and Inspection Center". The product quality has passed the IS09001 quality system standard certification. And obtained the qualification certificate for self-operated import and export. Over the years, Dingbo units have been widely used in all walks of life, and have won the network access qualification of the Ministry of Information Industry, the network access qualification of the Ministry of Radio and Television, the network access qualification of CNPC, the network access qualification of China Mobile, and the manufacturing qualification of marine units. In 2016, Dingbo was awarded the Certificate of Qualified Supplier of China Nuclear Power Group. Dingbo Generator has been cooperating with Shangchai Power for many years. In 2009, it became the OEM partner of Shangchai Power in China. Dingbo generator VOLVO unit ranks the top three in the Asia-Pacific sales volume, and is the core OEM partner of Sweden Volvo in the Asia-Pacific region. If any question please feel free to visit our website https://www.dieselgeneratortech.com/ or send email to [email protected].