As I get closer finishing assembly my two cylinder T engine (cut in half), I wonder how much oil might be too much---or not enough, while it is running.
So my thought was to fill it so when the rod throw on the crank is fully down, to fill it so the level is half way up the rod journal. My only fear is I don't want to "whip: the oil into a foam, but obviously fill it enough so everything gets splashed and lubricated as there is no flywheel in oil or funnel to bring oil forward like on a stock T.
The reason why I want to also know is I want to add a petcock for checking and need to know where height wise in the pan to use it.
So maybe some of you small engine or hit and miss engine guys can help?
On my Novo hit and miss the instructions say fill the crank case until the rod cap nuts just hit the oil on the downward stroke. That's one example I am sure you will get more.
Over filling can cause broken parts (crank, rod) in higher rpm engines. In low speed terms; The Model T crankshaft will hit a non-compressive fluid (the oil) at about 20mph at 1000rpm. To put that in human terms; It's like you doing a face down belly-flop off a 10 meter diving board about 16 times per second.
As George says, keep the entry into the oil at a minimum. It will splash.
All good info, I think I will set the level a little bit lower then---perhaps to the bottom of the rod nuts as suggested.