Yamaha F150 impeller plastic housing

[kevind]

I am in the process of replacing the impeller and I noticed a couple of things. The plastic housing has about 1/16" drill hole going from the inside to the outside. I'll attach some pics. In the 3rd pic you can see the hole going from the inside to the outside on the left side of the pic. Is this normal on other housing it's the first one I have done so not sure. I don't believe so as it was filled with some type of caulking. Also there was a collar on the shaft above the impeller. Looks like a cap with a plastic insert under it. The plastic was in pieces but from all the videos I've seen I haven't noticed anyone removing one. Is it needed?

 

[kevind]

Just an update. Bought the new parts. hole comes from the factory that way new part has it. For some reason the plastic melted and that must have been what looked like caulking plugging the hole. For 40 bucks not worth cleaning up the old part will put in the new one plus the plastic collar ring that goes over the impeller with stainless cap.