Warm water in bilge after outing

[jkimball]

So, again my first I/O and I'm learning quick how much I loved the "problems" of an outboard. But if I could get all the little bugs worked out this would be a great boat. She runs amazing, aside from the typical 4.3 warm start problems (and has low rpm stalled twice) but other than that once running, runs like a scalded cat!
But I digress.
What I've found I need to focus on right now it's the fact that after each outing, normally of 2 hours or more when I pull the plug at the ramp, there's warm water in the bilge. Normally it'll drain for 15-20 seconds so it's not a ton of water, and the bilge pump never comes on either (yes it works) but in my opinion any water in the bilge that I didn't put there is a bad thing.
Also, there seems to be a bit oil in it too. Not a lot but definitely there. Now this could be from the PO changing & spilling oil in the bilge, or I also have a trim line that had a small leak, that was supposedly fixed but I'm going to keep an eye on. So maybe it's residual? And just now all flowing out?
But the biggest concern is definitely the warm water. I don't have any temp spikes or anything. The gauge stays around 170*
Thoughts?
Oh. It's a '97 Merc 4.3LX Alpha Gen+

 

[Bt Doctur]

Normally it'll drain for 15-20 seconds so it's not a ton of water

Wrong, that is a lot of warm water. warm water is an active leak from:
drain plugs, leaking hose, loose hose clamp, cracked block., leaky Y pipe

 

[Scott Danforth]

Start by cleaning the bilge to rule out residual oil. Dawn dish soap and hot water works wonders.

Then, put boat in the water, fire it up and thoroughly look for leaks using mirrors, flashlights, and your cell phone camera

 

[thumpar]

Since it is warm water you could try running it on muffs to see if there are is water coming from somewhere on the motor. If you don't find anything put it in the water and start looking. Like Scott said, use whatever it takes to find it. That is not a small amount of water. On mine it might drip a bit but that is after the kids getting in and out of the boat swimming.

 

[Chad Flaugher]

The engine compartment gets very warm, including the water in it. I wouldn't rule out transom penetrations such as steering cables, transducer cable, drain plug bung, the boot, etc... Lots of good advise already... Clean thoroughly, and get it on the lake with a very bright spotlight, a mirror, phone camera, etc. If you don't have people getting in and out of the water, then you have a leak and it'll show itself if you look hard enough. Hope it's not a big deal!

 

[jkimball]

So a quick update.
I appreciate all of the good advice, and I need to scrub it all down with hot water and dawn so that I know any oil in the engine compartment is gone. Now, if it migrated to other parts of the bilge I'll have to somehow deal with that later.
But on the water part of this problem. When we got home from church, I put the plug in, put the muffs on and ran it for about 15 minutes and didn't see any leaks from hoses or the engine. So after I shut it down, no water in the bilge.
This leads me to think I have a through hull or a bellow leaking. When I bought it, the mechanic said the bellows were ok,but he also removed the drive to replace the LU lube monitor hose and trim senders but didn't replace the bellows because he said they were fine. Instead he just put them back on, replaced the metal ring and here we are.
Could this be the problem and will it be easy to spot?

 

[tlewis1]

With drive trimmed up you should be able to look under with a light and see the 3 bellows. Typically water leaking could be the U-joint bellows or shift cable bellows are ripped or possibly fallen off. Next time the boat is on the water I would have a really good look around the inside transom and look for leaks as well as while someone else is driving the boat you can be in the back looking for leaks.

 

[JASinIL2006]

To clean your bilge, put in your plug, pour some hot water and Dawn inthe bilge, and go for a drive for 15 minutes. Drain and rinse.

 

[Volphin]

I had a leak at one of my exhaust elbows that did this. I forgot to double check the clamps. DOH!

 

[H20Rat]

The engine compartment gets very warm, including the water in it. I wouldn't rule out transom penetrations such as steering cables, transducer cable, drain plug bung, the boot, etc... Lots of good advise already... Clean thoroughly, and get it on the lake with a very bright spotlight, a mirror, phone camera, etc. If you don't have people getting in and out of the water, then you have a leak and it'll show itself if you look hard enough. Hope it's not a big deal!

Depends on your boat I guess, but any water I splash in comes out relatively cold. The temperature of the fiberglass, which is cooled by the lake water, affects the temperature of the water in the bilge more than the engine.

Easy solution, run the engine on a hose... See if water comes out of the bilge on the trailer.

 

[jkimball]

So, after cleaning the bilge today, I think I may have found my source of water in the bilge. I'm somewhat relieved, yet a little concerned. I found that one of the 3 screws in the garboard plug is leaking. So, it's nice to know that I don't have a "major" leak, and it is something that should be super easy to correct. Worst case is turning the drain 60 degrees and re drilling the screw holes.
However, it concerns me about how long it has been going on and if there is any damage to the inside of the transom from the leak. Everywhere I checked on the transom when I bought the boat sounds solid, and still does... so I think I'm ok. But, in the event there is some water infiltration, is this correctable without a transom replacement in the (hopefully distant) future? All sounds well, and the leak is extremely slow, but definitely there.
I don't think I have rot, it all sounds solid, so I hope I'm fine and I caught it in time. But, in the event I do have something bad growing in there, I've heard somewhere that antifreeze will kill the rot fungi, and I could just inject epoxy in the area to restore it. (Again, IF I have a problem, right now there isn't a sign of it)

 

[Lukelona]

One screw is leaking and it pumps for 15-20 seconds? That doesn't sound quite right. I'd bet you have multiple leaks and your screw leak is minimal. I'd start with trying to tighten the screw, if it strips out easily, chances are there's rot around the plug.
Hopefully not, and in the case that it's good seal it up with 3m 5200 or 4200. DO NOT use silicone, it will fall right off.

My boat had a similar leak recently and was a corroded y pipe, had to pull engine to replace.
Could just be the y pipe o ring also.
to rule this out, carefully reach your hand down to the ypipe flange while running on muffs and feel for hot water leaking.
If not there, check all your cooling hoses connections and winterizing drain plugs.

As far as the oil in bilge, could be power steering fluid (if equipped) trim fluid, or oil pan gasket could be leaking. Clean bilge well and watch for further accumulation.
I like using de-greaser and hot water with plug in, let sit, rinse and repeat

Good luck

 

[jkimball]

So, just an update. I found that it wasn't just one screw leaking - it was the whole garboard assembly.

It looked pretty questionable to begin with like someone just smeared caulk all over it, but didn't look like it'd leak.
So I tried to tighten the screw down - tightened fine.... Checked all the others and same result. I could actually wiggle the plug flange just a little if I tired. So I think this was my problem.
I pulled it off, scraped all the mystery goop off and resealed with 5200, filling all the screw holes as well then tightened her back down and cleaned up my overflow.

Hopefully this fixes it, seems it should.

Now, the question is how long before I can use it? Since not under any direct pressure can it go in the water immediately? Since supposedly 5200 cures under water

 

[Lukelona]

Technically yes you can use it right away according to 3m. But I've found if you use 5200 and get it wet immediately, it can come loose. I would wait 24-48hrs min.
That stuff hardens like a rock (almost, still flexible) and works great.

 

[pro-crastinator]

7 day full cure. Some guys mist it with water. I rely on moisture in the air.
gloves and paper towels are a must have. 5200 is an evil product that works great.

 

[Rick Stephens]

Had a keel guard that was flapping loosely under the hull right at the transition from the bow (right where it touches first if you beach the boat). Used 5200 to reattach it, that was 5 years ago and still looks like the day I put it on. I didn't think that stuff was EVER going to cure!