Any boat motor mechanics here?

[Throbbinhood]

Any boat motor mechanics here? Chasing a weird water leak and would rather have an idea of what I'm looking at before I strip the thing.

[MB]

Not a mechanics behind sorry mate, let alone my Tinnie’s motor too. Best to describe where she’d be leaking from, I’m also keen to learn!
Maybe a simple cooling (river water) outlet hose is stuffed/perished and leaking back in the housing base hopefully?


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[Throbbinhood]

I’ve got a 1999 Honda BF9.9a (BABS-1400514) that is weeping water from the area highlighted in the below photo.

1.jpg

I believe this is the exhaust, and this image from the service manual confirms that water travels through the exhaust on this motor

2.jpg

I believe the part highlighted in yellow below is the cause of my problems

3.jpg

If it is not the rubber seal, then it’s likely the exhaust itself has a crack somewhere.

4.png

Should be part 18 I'm hoping. If the exhaust itself is cracked then it will be significantly more costly unless I can weld it or similar.

This video (not mine) appears to show the rubber seal in question, if you need a better look: https://www.youtube.com/watch?v=0lQD...youtu.be&t=430

The following link has some good parts diagrams for this motor, but the labels are a little misleading at times.

https://www.boats.net/catalog/honda/...99999/oil-pump

I believe to repair this I will need to remove the motor from it's housing (I believe that the seal is on the motor side, not on the mid section side). I'm hoping this won't be too difficult. I have basic mechanical skills (have rebuilt cv's wheel bearings that kinda stuff), but we shall see. If anyone has done anything like this, any input or advice is welcomed.