Too much oil in crankcase?

[Fuzz]

A friend inadvertanly put about 3 qts too much oil in a Dodge Intrepid.

When he started it up it had a loud knock. . Shut it off,and noticed what he had done. . drained the oil out and filled with proper amount. The knocking stopped. .

Why would too much oil do this. . ?Just trying to further my feeble education. . Thanks.

 

[RustyJC]

Probably because the crankshaft/connecting rods were hitting the oil in the pan and frothing it up. If the oil pump is pumping foam (i. e. , oil and air) through the system, it can't form a hydrodynamic film to provide proper lubrication for main and rod bearings, etc. Neither can it provide a good "fill" for hydraulic lifters, so they will collapse when filled with foam.



Rusty

 

[Fuzz]

Thanks

Thanks for that explanation,Rusty.

Makes sense. .

Fuzz