prolem changing final drive oil, need advice

I'm changing the oil in the final drives on my cat 315. One side went fine and now I'm ready to fill the other, the problem is there is something inside the fill hole blocking my oil spout from going into the hole. I can get a hose to fit in there if I need to, I just wanted to check if this is something I should be concerned about since the first side was not like this.



Thanks in advance,

Matt