Engine lube ?

[Camprunner]

In a modern car/truck engine are the main bearings sitting in oil? In other words is the oil in the pan go up to the mains? If not how do mains get there oil is it injected somehow?

 

[zfasts03]

Main bearings are not sitting in oil. The pressurized lubrication system supplies oil to the main and rod bearings and other vital parts by supplying oil though galleries (small passage ways).

 

[OneEyeJack]

If the oil went all the way up to the mains the crankshaft would whip up a big aerated mess of foam inside the crankcase.

An oil pump picks up oil in the pan below the crankshaft, rod and main bearaings in a wet sump engine and pumps it everywhere it needs to go for both pressure and splash lubrication.

Here's a 1937 video from Chevy that show an old fashioned oil system with "dippers" on the rod bearings. Modern engines no longer use a "dipper" but this will show you how it all works.

 

[Camprunner]

Got ya! .. Thanks.