Originally Posted By: SteveSRT8
I am not aware of a single contemporary automobile engine in ANY car that uses splash lubrication for the piston, rings, bores, etc.
Can anyone name one?
Most automakers go to great lengths to isolate the spinning crank from the oil and avoid splash, as it wastes power/economy.
Yes, crankshafts certainly don’t run in the oil these days. All four-stroke engines now have oil pumps.
But in ye olde days, crankshafts in some engines did indeed dip into the sump to pick up oil and splash it about. Such engines had no oil pumps. Power outputs from those engines was low. Longevity was low, too.
Later on, some motorcycle engines had a positive oil feed to the cylinder from the oil pump.
This practice was discontinued when it was realized that a rotating crankshaft with oil pressure-fed to its big end bearings did a pretty good job of spraying oil around the inside of the engine. Even if you haven’t seen inside a running engine, it’s really not hard to imagine.
Whether you call this “splash” or “spray” or whatever does not alter the fact that it takes some time to get oil to the pistons, rings and bores. Mostly, the old word “splash” is still used.
Based on my observation, it does not take long to get oil splashed around, around 15-20 seconds.
That is why you should let an engine run for 15-20 seconds before moving off.
Every engine today that I know of relies on splash for some of its lubrication. How else does oil get to the bores, pistons and rings? They’re not pressure-fed. Wrist pins also get lubricated by splash. They’re not pressure-fed. Simply put, splash matters.
If you want to do movie-star starts on dry pistons, because you won’t wait those vital 15-20 seconds, I recommend you use an ester-based oil. Those oils have good ‘cling’ so that you don’t start up on a dry engine. There’s always some oil sticking to the engine interior, by polar attraction, even after shutdown.
