Here's the schematics. The first one is the levers. Number 41 is a seal. I can't imagine enough pressure to let that much oil out of that one that quick.
The second one is the cover. 51 and 52 are tubes and O-rings. If memory serves me right there are six of those tubes and 12 O-rings? If one of those blew out and then the oil blew through the gasket,it would likely dump a lot in a hurry.