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Yamaha Outboard Water Hose goes to nowhere

I don't understand how my 2002 90 HP 2 Stroke TLRA has worked these last few years. I'm chasing a different problem but when I took the lower unit off I was expecting to have to disconnect the water hose that pushes water back up to the engine from the water pump. It isn't connected though. However, somehow when I run the motor in the water it still has water spray out of the place its supposed to. I noticed that other people's engines online have a clean looking stream come out of the engine, but mine has always sprayed wide but figured as long as water is coming out oh well.

So I looked at the parts diagram it looks like there's a water hose that goes... no where. Even says it ends at "End, Nipple".
https://www.crowleymarine.com/yp/ZJ902160/lower-casing-drive-2-90tlra-2002-90hp Part 27

I don't understand what the point of it is, and it seems that the person who owned my boat before me also didn't considering it was just hanging off of the back of the engine doing nothing. You can see it laying on the boards, it's never been actually connected but the engine has always still cooled with water spraying out.

I also was wondering what the point of Part 11, it is called a Damper, Seal. The location where I found it seemed to be corroding out. Not the seal itself but where it sits. There was a lot of buildup there but as I used a toothbrush to get it out I noticed it looks like its corroding away the metal. I was wondering what would happen if that thing wasn't set properly and whatever it was sealing was failing what would happen.


corrosion.jpglowerUnit.jpghose.jpg
 
I've answered some of my questions. I see now where the water actually goes back up to the engine so that explains why it always worked. Also, on youtube someone asked the same question the smaller hose and someone said that was for a speedometer. I don't have a speedometer on my boat (what's the point on a pontoon...).

The part I still don't quite understand is the damper seal. The rubber part that sits down next to the water pump. On the youtube video the guy replaced them because they looked corroded like mine. I plan on replacing it but I don't know what the heck it does and what would happen if I don't.
 
That hose is actually the pressure feed to the speedometer if you boat is so equipped. It is not part of the cooling system. If you look at the leading edge of the lower unit just above the gearbox you will see a ~1\16” opening that feeds water pressure into the tube which the operates the speedometer.
 
That question is asked here about every 3 weeks or so.----That wee hose is for a speedometer.-------My project boat will be using a GPS speedometer with just a 12 volt lead going to it.-----No need for stone age plumbing.
 
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