What is this part I’m missing?

[Kfoehrkolb7860]

Hey guys. Just getting around to running my engine I rebuilt last year and I found this hole where something was mounted. It goes directly into the crank case. 440357Mercury 2.5 carbureted. Thanks.

[Whaaaaat]

Mechanical fuel pump. Plug the pulse port if your not using a pump( hole without threads)

[LakeFever]

NVM, I was tree'd and wrong ha

[Kfoehrkolb7860]

Okay cool. I was thinking it was something like that. Thanks!