Seal on driveshaft on top of impeller housing?

[DangerNewb]

Chasing a low water pressure / heat issue on Merc 280. Figured out I needed to use the 3/4 impeller housing but still struggling. Is there a seal that goes on top of the pump housing onto the driveshaft? Seems like there should be something there but I don't see anything looking at parts diagrams. My impeller is very good condition. Low hours. Little bit of "memory" with the fins bent some when I take it out of the housing.

I looked through some spare parts from an old CLE case that blew up and there's a rubber ring that fits on the driveshaft that could slide down onto the pump housing but it's just a rubber ring with flat sides. Doesn't seem like it would do much.

Any advice is appreciated.

[largecar91]

The rubber ring with flat sides is it. Slides down driveshaft to top of pump housing

[DangerNewb]

Thanks Largecar. I'll try it. Any comment on why it's not shown on the parts diagram?

https://www.crowleymarine.com/mercur...cfm?mdl=DKACQO

[rochelle howell]

That thing is called a "slinger" by mercury if I remember correctly. Wondered about it's degree of usefulness when I saw my first one.
Thought it was possibly a mis - placed item from previous owner / mechanic.
I've seen it listed on someone's diagram, but can't remember who!

[DangerNewb]

funny it would be called a slinger. Seems "non-slinger" would be more appropriate. I installed the one I had and installed the lower unit. Hope to test soon. The rubber washer/oring was pretty tight on the drive shaft. Seems like it would get hot and come apart from the driveshaft spinning. Drive shaft diameter on a 225 promax is same as a 280? The one I had laying around was from a 225 Promax. I intalled on a 280. Still seems like something doesn't make sense. Thanks for the feedback.

[DangerNewb]

This is what mine looks like that I found from spare parts from an old motor. https://www.crowleymarine.com/parts/1632.cfm

[rochelle howell]

Yep, that's it. Bet more than a few people scratched their heads over this part

[DangerNewb]

Does it stay stationary as the driveshaft spins? Looked like there was a flat spot up in the mid where it would seat. But I don't see how it wouldn't get super hot if it stays still with the driveshaft spinning inside. Mine was tight on shaft. Or does a little water from the pump housing splash on it enough to cool? Grease on inside on install? Anyhow, I'm hoping to test it out and see if my water pressure improves.

[transomstand]

It spins with the shaft. Just stops debris from falling into the water pump. Not the most essential part, I've gone without it several times.

[DangerNewb]

Ok. So not really going to help out my low water pressure I guess.

[transomstand]

No effect at all on pressure.

[rock]

It's especially effective on a mid with no liner. The pump leaks out the top and the slinger slings water in all directions across the water pump housing somewhat protecting it from the exhaust heat.

Rock