Draining Mystery Water

l008com

Senior Chief Petty Officer
Joined
Jun 14, 2007
Messages
751
I've noticed lately that when I get in from a boat ride, I have water in my bilge.


These are typically about 3 hour boat rides. These are days when theres minimal waves and wind, and I'm mostly on rivers anyway so I am sure no spray is coming in.

The plug is nice and tight. I use a wrench, that part just got cropped off the video. When not boating, the boat is parked on land and the plug is pulled. So the water definitely gets in there during the boat ride.

So clearly something is leaking, but what? How do you even track something like this down? The bilge/lower deck is like 3 inches thick so it's not like I can "climb down there" and take a look.

It's a small boat, as seen here:
IMG_0002.JPG
 

briangcc

Commander
Joined
Jul 10, 2012
Messages
2,360
It was dripping pretty good before the drain plug was removed. What's the underside of the hull look like? Boat been beached alot??

I'd look very carefully under the boat to see if there are any punctures/gouges in it. That checks out, I see alot of rust staining on the outboard mounts. How's the transom??
 

l008com

Senior Chief Petty Officer
Joined
Jun 14, 2007
Messages
751
You can buy a cheap phone "camera/scope" to get into odd areas.
This one is from Amazon for $18.00.


View attachment 367679
I've thought about that, that would be handy to have. Still it might be tough in this case, unless the plug/plate itself was leaking. Its going to be pretty hard to 'steer' that thing around underneath the floor.
 

l008com

Senior Chief Petty Officer
Joined
Jun 14, 2007
Messages
751
It was dripping pretty good before the drain plug was removed. What's the underside of the hull look like? Boat been beached alot??

I'd look very carefully under the boat to see if there are any punctures/gouges in it. That checks out, I see alot of rust staining on the outboard mounts. How's the transom??
Everything looks fine. The boat is pushing 40 so who knows what it's seen. But it looks like it's in pretty good shape. I'm under the boat a lot, usually fixing the trailer wiring. There's nothing obvious to me.

Also what outboard mount? You can't even see any part of the motor in this video. Not really sure what you're asking, with 'hows the transom'. Looks fine to me. Looks fine in the video. There are no holes in it I can see, i mean except for the holes that are supposed to be there.


Also a note to all, not related to the reply above: Regarding the amount of water. While it looks like kind of a lot, note that it's coming out continuously but pretty slowly. It's not even enough water to get my pump to stay on. So it is definitely a slow leak. It would probably take all day for a whole gallon to leak in. That said, of course I'd still prefer to fix it if I can.
 

Baylinerchuck

Commander
Joined
Jul 29, 2016
Messages
2,726
I would remove the plastic drainplug plate.------Inspect that.-----Reinstall the 3M sealer 4200 or equivalent.
I agree go for the most obvious places first. Look for pin holes or cracks in the hull, pull the drain fitting out and reseal, look at the lower through bolts for the outboard. There’s not a lot of places on that boat for a leak.
 

briangcc

Commander
Joined
Jul 10, 2012
Messages
2,360
Also what outboard mount? You can't even see any part of the motor in this video. Not really sure what you're asking, with 'hows the transom'. Looks fine to me. Looks fine in the video. There are no holes in it I can see, i mean except for the holes that are supposed to be there.
Your camera catches the lower part of your outboard bracket. There's rust stains, presumably from your mounting bolts on the transom. It's visible at the very beginning of your video.

The comment about your transom is that if its flexing it will let water in as its not sealing properly.

Looks are one thing, drill testing shows the real truth about the health of your transom. Have you sampled your transom to ensure its not part of your issue? From the inside of the boat, as low as you can get, use a 1/4" drill bit and without going through the outer skin drill some test holes. If the shavings come out wet, you have a transom issue. If they're dry, seal with some4200/5200/marinetex/epoxy and move on to finding the culprit.
 

Baylinerchuck

Commander
Joined
Jul 29, 2016
Messages
2,726
Also what outboard mount? You can't even see any part of the motor in this video. Not really sure what you're asking, with 'hows the transom'. Looks fine to me. Looks fine in the video. There are no holes in it I can see, i mean except for the holes that are supposed to be there.
The transom is a wood core encapsulated in fiberglass. The bolts that go through the transom can and will leak over time causing the wood to rot. Especially the lower outboard mounting bolts since they are below the water line at times.
 

l008com

Senior Chief Petty Officer
Joined
Jun 14, 2007
Messages
751
Your camera catches the lower part of your outboard bracket. There's rust stains, presumably from your mounting bolts on the transom. It's visible at the very beginning of your video.
I think you're just seeing shadows from the street lights. There is no rust there at all. Plus I trailer the boat so it's almost never just sitting in water. And the motor was removed by a professional a few years ago when I got a new steering system,he bolted and glued it all back in place and there was no issue then. And due to boat ramp parking issues, there hasn't been much boating. Point being I think its very unlikely this has anything to do with the motor mount. Probably more likely the plug needs to be resealed or maybe theres a crack in the hull that happens to be under one of the rollers on the trailer so I never see it when I look.
 

airshot

Vice Admiral
Joined
Jul 22, 2008
Messages
5,080
what about collecting rain water from sitting outside....you mentioned removing the plug when it sits on the trailer. ????
 
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