What to do if the oil filter has no pressure difference?

When the oil filter has no pressure difference, the oil may not be filtered normally, affecting the operation of the equipment. The following is a step-by-step troubleshooting and solution:

Check whether the system is operating normally

- Confirm the power supply and pump operation: Check whether the oil filter power supply is connected, whether the oil pump is started normally, and whether the motor has abnormal noise or stops.

- Observe the oil circuit valve: Make sure that the inlet and outlet valves are fully open, and the pipeline is not blocked or closed by mistake.

Troubleshoot the differential pressure gauge or sensor failure

- Check the differential pressure display device:

- If it is a mechanical differential pressure gauge, tap the dial to observe whether the pointer is stuck, or temporarily ｒｅｐｌａｃｅ a new gauge for testing.

- If it is an electronic sensor, check whether the line connection is loose, and try to reset or calibrate.

- Short circuit test: After turning off the equipment, short the differential pressure sensor signal line, simulate the differential pressure signal, and confirm whether it is an instrument failure.

Check the status of the filter element

- Is the filter element blocked or ineffective?

- A completely blocked filter element may cause an extremely high pressure difference, but if the filter element is damaged or not installed in place, there may be no pressure difference.

- Remove the filter element to check whether it is damaged, deformed, or the seal ring has fallen off, and ｒｅｐｌａｃｅ it with a new filter element if necessary.

- Filter element model matching: Confirm whether the filter element accuracy and specifications meet the system requirements (such as flow, viscosity).

Check the oil circuit and flow

- Oil fluidity:

- High viscosity oil may cause poor fluidity at low temperatures. Check whether the oil temperature is too low and preheat if necessary.

- Confirm that the oil is not emulsified or seriously contaminated (such as too much water or impurities).

- Insufficient system flow:

- Check whether the oil pump is worn, whether the oil suction port is blocked, or whether there is leakage in the pipeline that causes insufficient flow.

Eliminate air or leakage problems

- System air intake:

- Check whether the oil suction pipe is leaking (such as loose joints, aging seals), and whether there are bubbles when the oil pump is running.

- Exhaust air at the high point exhaust valve of the oil filter.

- Pipeline leakage: Check whether there is leakage in the inlet and outlet pipelines and joints of the oil filter, which makes it impossible to establish pressure.

Verify the oil pump and overflow valve

- Oil pump output pressure:

- Use a pressure gauge to measure the pump outlet pressure. If the pressure is too low, there may be wear inside the pump or a faulty overflow valve.

- Overflow valve setting:

- Check whether the overflow valve is misadjusted or stuck in the open position, causing the oil to flow back directly and unable to establish a pressure difference.

Other possible reasons

- Parallel filter bypass valve failure: If the system has a bypass valve, confirm whether it is opened by mistake (such as a broken spring or a stuck valve core).

- System design problem: In rare cases, the oil filter selection does not match the system flow (such as the filter flow is too large), and the parameters need to be recalculated.

Temporary measures

- If oil is urgently needed and cannot be repaired immediately, the oil filter can be temporarily bypassed (make sure the oil cleanliness allows), but repair it as soon as possible to avoid equipment damage.

Summary steps

1. Confirm whether the instrument is normal → 2. Check the filter element and seal → 3. Check the oil pump and valve → 4. Eliminate air/leakage → 5. Verify the oil status.

If the above steps still cannot solve the problem, it is recommended to contact the equipment manufacturer or professional maintenance personnel for further diagnosis.