Questions - 2007 Yamaha HPDI 250 - Oil Alarm

Running Lewisville this evening when I got an oil alarm. Shut it down and limped back to the dock. Noticed that my Oil cap was cracked when I got back. I have a couple of questions... 1.) does the oil cap being cracked (pretty bad) affect the alarm. I figured that the cap allowing Air into the tank would make it tough to keep the vacuum seal good. 2.) How might I go about finding a part number for the cap so that I can order a new one? Thanks for the help!!!

-Will

Yamaha has a pump built into the main oil tank. The crack won`t stop the oil. Look at the bottom side of the main oil tank. Has a small inline filter.