Having one of the two square O rings on the oil transfer pipe blow out is not on the list of things I like to see or to have happen.

Correcting that particular problem involved going through an assortment of transfer pipes and finding one that really fit into position snugly; and which seated the square O rings firmly and deeply in the passages.

The fact that there could be such a backpressure on the circuit to cause a seal blowout really began to nag at me in the back if my mind. Sure, I could have just chalked it up to the transfer pipe not being a nice, tight fit; because the ill-fitting pipe was the "actual" cause. The little voice kept asking: but what if there is more to it than that?

So I decided to check it out further. And I am glad that I did.