Water in bilge

[gregwco]

2000 Larson 176 3.0 liter sterndrive. After purchasing this boat, I read that some larsons take on water. This one takes on in my opinion a lot. This is my first sterndrive. It takes on much more water when running at higher speeds. I can not find the source of the leak. I have run it with the platform up and can not see any water coming in or leaking from the cooling system.
Thank you for the help, Greg.

 

[Nheels]

That's a difficult question to answer as there are a million places water can enter. Have you looked around the transom?

 

[JASinIL2006]

Where did you read that some Larsons can take on water? I've never heard that... seems to me that a boat should not take on water at all.

How much water are you accumulating over what period of time?

 

[ThomW]

Does it accumulate water while just sitting in the water, or only when you are running it? If it's the latter, then it would seem like its leaking from the motor's cooling system. If it takes on water while just docked...its probably leaking from another point.

 

[gregwco]

Yes, I have looked around the transom. All the fasteners look to have never been touched. I can not see any water intrusion while underway. Nor any water leaks from the engine or cooling while underway. Most of the water seems to accumulate over 3500 rpm. Under that rpm, I will get some but not a lot maybe quart. If I run it 4000 for over 10 minutes, gallons of water.
I had thought that the sterndrive to transom had a leak, separating during higher RPM. Thinking it had been worked on and reinstalled improperly. As I said, the fasteners look to be untouched. My other thought is after 22 years the seal between the drive and transom has deteriorated. I'm unfamiliar with the possibility of this.
Thoughts on this or procedures for finding where the water might be coming from?
Thanks, Greg.

 

[JASinIL2006]

If it's happening only when underway, it might be the seal around the rubrail has deteriorated and water is getting in there... that seems a long shot, though.

 

[gregwco]

Possibly, but with the location of carpet in the boat and it is not wet. The water from rubrail would be soaking carpet.
Thanks, check off one.
I appreciate all input. For me it's a great way to trouble shoot. I can't number how many times a what about this leads to the light coming on.

 

[poconojoe]

Could it be a through the hull fitting? Do you have a bait well?

Are you sure it's not a leak in the cooling system? Could be from a fitting or hose that is hard to see. Maybe blocked from view and as you increase RPM, the leak intensifies.

Can't be bellows since it only happens when you're on the move. You're sure of that, right?

 

[JASinIL2006]

Could it be a through the hull fitting? Do you have a bait well?

Are you sure it's not a leak in the cooling system? Could be from a fitting or hose that is hard to see. Maybe blocked from view and as you increase RPM, the leak intensifies.

Can't be bellows since it only happens when you're on the move. You're sure of that, right?

That's actually an interesting possibility. When I rebuilt my Larson and reinstalled the engine, I had a couple of hose clamps that weren't tight enough, but they would only leak above 3000 RPM, so everything looked fine when run on muffs. When the boat was in the water and run harder, though, I got trickles of water. One more thing to check and rule out...

 

[gregwco]

I'm going to setup an action cam (DJI), like gopro. Maybe I can capture it on a video

 

[JASinIL2006]

I'm going to setup an action cam (DJI), like gopro. Maybe I can capture it on a video

Seems like a good idea!