2. Start the engine. If oil is flowing from the oil pump, you will see it dripping from the oil filter housing.
3. Check the oil pressure. If the oil pressure is low, it may be a sign that the oil pump is not working properly.
4. Listen for any unusual noises. If you hear any unusual noises, it may be a sign that the oil pump is not working properly.
5. If you suspect that the oil pump is not working properly, you should have it checked by a qualified mechanic.
Here are some additional tips for checking the oil pump of a Mercedes-Benz 300D:
* Make sure the engine is cold before you start the test.
* Use a flashlight to help you see the oil flow from the oil pump.
* If you are not sure how to check the oil pressure, consult your owner's manual or a qualified mechanic.
