Hydolocked with oil?

[jkur10a]

Is there anyway for oil to enter the motor from the RV?

I'd like to know this as well, as I want to be as sure as possible which place is leaking and in turn filling my motor(s) with oil.

For those who added a valve to the oil line, did you use something like this? I'm having a hard time finding something online in the right size and an even harder time to find something made here in the USA.