Out of the blue my injector pump starting leaking diesel from what appears to be a small screw (see red line pointer) at the front side of the pump where it attaches to the front gear cover. To get to that area, I have to remove a tube that has a hex fitting at it's bottom, but then a strange nut (see red square) that is rounded on two sides and flat on the other two sides. Not wanting to break the nut and/or damage the injector pump, I'm reaching out to see if anyone knows of the correct tool to remove this nut and if this particular point where the diesel is leaking makes sense to anyone as well.

Appreciate any feedback you have.

 

Turns out that a universal socket works great for these nuts. Gets them off without any damage.

https://www.oreillyauto.com/detail/c...iversal+socket

Once off the screw where the leak was coming from was an easy fix as well.