water in the bilge... Hmmm?

[650Guy]

Ok, this is an odd one for me and am wondering your thoughts:

2003 Carver 396 aft cabin is my boat.

She was in heated storage for the winter and launched last week. The water temperature was 38F (these details will be brought up later)

A couple hours after launch I was checking my bilge pumps and bays, only to find water in the aft most bay near the drain plug. My boat has ALWAYS been dry as a popcorn... well, its dry! So this came as a bit of a shock to me to find water.

I used a hand pump to get as much water out of the bay as possible. water was not RUSHING in, by any means, but it was coming in. I would say it was growing at about 1/2 gal an hour. The next morning, the water was back and to a level where I believe the bilge pump had kept it overnight. I got a shop vac to completely dry the boat out and had sucked out a good 30 gal of water.

I was then with the boat for a good 3-4 hours and no additional water seemed to intrude or accumulate. I had to leave the boat, and will not be back for 3-4 days. (don't worry, my marina and friends are watching it for signs of trouble.

To add more details: no other area of the boat show any signs of water:
* All sea trainers were dry
* eng compartment... dry
* Fwd compartments .. yep dry

Here is my wonder

Could the rapid change in temperature (65f in the building to 38f water temperature) be enough to expose some issues with the drain plug? I don't believe there is any teflon tape on the plug but I'm guessing as I have never removed it or had the need as its always dry in there. My only thought is could expansion/contraction due to temperature played a small impact here where the drain plug (which is the only thing in the back area where the water was) played a part. Could 1 material not adjusted to the temperature change as fast as an another allowing the water to intrude and as it adjusted the leak stopped? seems far fetched to me, but about all I can think of.

[bud37]

QR_BBPOST Could the rapid change in temperature (65f in the building to 38f water temperature) be enough to expose some issues with the drain plug?

IMO, sure it could, anything is possible but unless someone disturbed it I doubt it could leak that much.....but my guess would be more the rudders and perhaps the strut support area.
Other culprits could be the trim tab screws, transom anode bolts, exhaust fittings etc.
If you do pull the boat, don't use teflon tape on the brass plug threads, use proper pipe dope......you can split those fittings with the improper use of tape.

If the water stopped then the assumption would be whatever it was, was capable of swelling....consider those areas.

[Cooler]

I would guess the packing is not expanding as fast as years past. Maybe due to the temp of the water. Doubt it is the drain plug. My boat takes some time for the packing to swell/seal in normal conditions. er

[650Guy]

Thanks so much for the thoughts and feedback!

So no tape… good to know! Don’t want to think of this.

As far as packing, I have dripless shafts so I really don’t have the old style shafts with packing and my entire engine bay is dry.

I can’t see the area where my starboard shaft support is mounted.

On Weds when I get back I’ll know if it stopped for sure.

[Viper]

QR_BBPOST ....I have dripless shafts so I really don’t have the old style shafts with packing and my entire engine bay is dry.....

Are your rudder shafts dripless too?

[650Guy]

I don't know, I will show my ignorance here and didn't know they could be? With this being said, here is the ODD part for me. The bays that the rudders are in, are dry. no water in those. it is just the center bay that seems to have water, I have done my very best to check all the bays port/starboard of the main stringers and they all seem dry. Its very difficult to get under the bed in the aft cabin though, so not completely sure those area's have no water, but the only thing I cannot see is the mount for the port side shaft support. that one is a bugger to get at.

This is what lead me to thinking it was the drain plug itself as it is about the only thing I can think of in that center bay AFT of the engine room. and the engine room is completely dry.

is that housing for the drain plug something that ever leaks? I imagine that is installed by drilling a hole, using some sort of 5200, installing the housing, and boom... you got a drain plug. MAYBE that 5200 sealant is starting to get old??? The marina folks said they verified the plug was tight prior to launch, if that housing sealant is starting to get old, maybe when they cranked on it, it loosened it enough to allow water to penetrate?

[plittle2005]

Short-haul the boat....see where the water runs OUT?

[tomschauer]

Does the water accumulate when you are hooked to dockside water?
Maybe it's a potable water leak?