why do i have diesel going into my oil

that engine has the 6 individual cam driven fuel pumpers. A failed pumper or orings. Fuel supply pump is gear driven & could also cause it.

 

This. EUP pump o-rings have been known to leak. Most common problem is fuel transfer pump, leaking fuel past drive gear seal.

 

Like these guys said, it could be a number of things. I wouldn't hesitate to fix it, though. I've been told that it will wipe out your bearings if it gets diluted enough

 

There is a plug in front of the block for fuel galley that has been know to leak into front cover

 

Having seen this before and repairing such issues on many occasions, I Would have to agree with others, injector 'o' rings would be first place to look.