Why Non-Detergent Motor Oil?

[Bayman]

I just wanted to add what make ND oil special. Detergent oil runs clean off of surfaces so it effectively cleans as it lubricates. Thus keep contaminates from building up on engine surfaces and keeps them fluid bound so the filter can remove them. It's why all automobile engines use detergent oil to prevent gunk.

Non Detergent oil sticks to surfaces and will always leave a protective layer of oil. When I built engines I would lubricate all the parts with ND30 because you have to turn the engine parts dozens of times and turn the whole thing over in the stand as you build it. The ND stays better on the parts and protectects them during assembly and initial start up. I could take days to build an engine and its fine with ND30. Had I used regular oil the engine would be dry and unprotected if it sat overnight.

Use ND oil if you want it to stay put and provide long service on parts without oiling systems. Use detergent oil on things with oil pumps, sumps and filters.

BTW transmission fluid is super high detergent oil. It doesn't stick to anything long.

My experience is 10 years building race cars and engines, 21 years a dealer mechanic, 11 of them as a BMW master mechanic and 15 years a railroad machinist.

[Artie]

I apologize for sidestepping air guns for the moment but am about to change the oil in my push mower:
"Non Detergent oil sticks to surfaces and will always leave a protective layer of oil."
So should a push mower with a small air cooled engine use ND oil?

[airgunaut]

Bayman, thanks for explaining what the practical difference between ND and other oil is.

I use food grade mineral oil to treat a raw wood rolling pin. Is this basically a version of thin ND oil that is rated safe for human ingestion?

[Mzq284]

I apologize for sidestepping air guns for the moment but am about to change the oil in my push mower:
"Non Detergent oil sticks to surfaces and will always leave a protective layer of oil."
So should a push mower with a small air cooled engine use ND oil?

Yes!

[mobilehomer]

I apologize for sidestepping air guns for the moment but am about to change the oil in my push mower:
"Non Detergent oil sticks to surfaces and will always leave a protective layer of oil."
So should a push mower with a small air cooled engine use ND oil?

Follow the manufacturers recommendation.

[avator]

I apologize for sidestepping air guns for the moment but am about to change the oil in my push mower:
"Non Detergent oil sticks to surfaces and will always leave a protective layer of oil."
So should a push mower with a small air cooled engine use ND oil?

Follow the manufacturers recommendation.

Thank you Ken.