Proper oil level

[imp]

Oil Level and "Safety"

"Safe" oil level is a moot point, in reality. So long as sufficient oil is present in the sump to prevent the pump from sucking in air, instead of oil, the engine is protected. Be aware that vehicle "bounce", tilt, uphill, downhill, causes changes to the oil level relative to the pump pickup.

Most important, is that the LESS oil in the sump, the HOTTER the oil will be while running. HOT oil is undesirable, relatively speaking. Running the engine with oil level at low end of acceptable on the dipstick, will result in somewhat hotter-running oil than at the "full" mark. Just my opinion. imp

 

[SoNic67]

I disagree... Higher level than necessary will cause lots of problems too. As the crankshaft rotates, it will churn the oil, causing aeration and eventually sustained foam may form. This can lead to overheated motor oil, oxidation and a loss of oil pressure. Spongy aerated oil is hard to pump. It starves the engine and critical lubricated surfaces.

 

[drbenz]

Imp and SoNic if you think about it you are both right. The more oil that is in the engine the cooler it will run, that's why some european cars take two gallons of oil to fill the crankcase but having said that, if you overfill the engine the oil will be whipped into a foam or at least get splashed in large quantities where it should not be. Moral of the story: keep it between the marks and you will be ok.

 

[imp]

I disagree... Higher level than necessary will cause lots of problems too. As the crankshaft rotates, it will churn the oil, causing aeration and eventually sustained foam may form. This can lead to overheated motor oil, oxidation and a loss of oil pressure. Spongy aerated oil is hard to pump. It starves the engine and critical lubricated surfaces.

Ah, but please note, I DID NOT advocate OVERFILLING with oil; rather I sought to point out that UNDERFILLING causes higher temperatures. Yes, as the rotational parts contact oil, regardless of it's source, it creates drag and aeration. However, your comments about aerated oil are very correct! imp

 

[imp]

Imp and SoNic if you think about it you are both right. The more oil that is in the engine the cooler it will run, that's why some european cars take two gallons of oil to fill the crankcase but having said that, if you overfill the engine the oil will be whipped into a foam or at least get splashed in large quantities where it should not be. Moral of the story: keep it between the marks and you will be ok.

Thank you! You said it best! imp