Slow leak H33 forward hull

[ish]

I have a 1977 H33 that has developed a slow leak somewhere forward of the bilge. The only below-waterline through-hull up there is the knotmeter, which I originally suspected but have all but eliminated by drying out the locker it is in (starboard V-berth) and stopping up the drain holes for a few hours... no new wetness accumulates. The forepeak and the port V-berth locker are both bone dry. Yet I have a steady, small trickle into the forward part of the bilge. I can't image what the source is unless the hull itself is leaking somehow--which strikes me as being a very bad thing.

The boat was holed on the starboard side amidships last year; the repair site is clean and dry, and the repairman ground out and refilled the full extent of the surrounding delamination. At the same time, he epoxied a gap in the hull/keel join at the leading edge of the keel which was pre-existing (and which did not leak previously). I inspected the repairs before it went back in the water and they looked good to me. Moreover, the water forward appears to be coming in above where the hull/keel join is at, trickling in from between the liner and the forward part of the hull.

The leak is definitely saltwater, so I'm ruling out the water tank or any rainwater intrusion.

I am at a loss as to where this could be originating or how to find it. The leak rate is so miniscule that traditional ideas like tracing bubbles or overpressure don't seem likely to work. Nor does flooding the hull with the boat out of water (since I would have to flood it above the woodwork!). With the liner in the way, it's impossible to trace the stream forward to a source. Can anyone give me any suggestions how to proceed? I would prefer not to start cutting the liner away but I don't know what else to do. Even if I did so, would that necessarily tell me where the water is coming in from the outside of the hull? Or could it be following a twisting path of cracks invisible to the naked eye? Can anyone who has ever had the liner out up there comment on how easy/hard it was to pull out and replace, and what exactly I will see if I cut it out?

Any input would be appreciated! Thanks.

 

[Joe23455]

I have a 1977 H33 that has developed a slow leak somewhere forward of the bilge. The only below-waterline through-hull up there is the knotmeter, which I originally suspected but have all but eliminated by drying out the locker it is in (starboard V-berth) and stopping up the drain holes for a few hours... no new wetness accumulates. The forepeak and the port V-berth locker are both bone dry. Yet I have a steady, small trickle into the forward part of the bilge. I can't image what the source is unless the hull itself is leaking somehow--which strikes me as being a very bad thing.

The boat was holed on the starboard side amidships last year; the repair site is clean and dry, and the repairman ground out and refilled the full extent of the surrounding delamination. At the same time, he epoxied a gap in the hull/keel join at the leading edge of the keel which was pre-existing (and which did not leak previously). I inspected the repairs before it went back in the water and they looked good to me. Moreover, the water forward appears to be coming in above where the hull/keel join is at, trickling in from between the liner and the forward part of the hull.

The leak is definitely saltwater, so I'm ruling out the water tank or any rainwater intrusion.

I am at a loss as to where this could be originating or how to find it. The leak rate is so miniscule that traditional ideas like tracing bubbles or overpressure don't seem likely to work. Nor does flooding the hull with the boat out of water (since I would have to flood it above the woodwork!). With the liner in the way, it's impossible to trace the stream forward to a source. Can anyone give me any suggestions how to proceed? I would prefer not to start cutting the liner away but I don't know what else to do. Even if I did so, would that necessarily tell me where the water is coming in from the outside of the hull? Or could it be following a twisting path of cracks invisible to the naked eye? Can anyone who has ever had the liner out up there comment on how easy/hard it was to pull out and replace, and what exactly I will see if I cut it out?

Any input would be appreciated! Thanks.

Just a thought, I have a 1980 36, for two seasons i kept getting a trickle,less than a rag full of water under my head sink or next to my V berth starboard side bildge area.Could not find anything. Finally on a starboard,following quarter sea,coming up the south jersey coast, I noticed my head sink throughull dripping. Today,sunday, I backed the nut off to re-bed and the through hull broke off ,,,, so glad it did not do it off shore. So check through hulls even close to waterline, I am replacing mine this week.(wood plug now in hole) Just my 2 cents

 

[ish]

Thanks Joe. Yeah, there's really only the one up there that I checked... nothing else even close. Plus, it accumulates at the same rate whether I am tied up at the dock or out sailing, so it really can't be a "now you see it, now you don't" sort of leak.

 

[Paul F]

salt water?

There is so little space that you have not checked. All I can think of is under the small floor liner into the v-berth. Does the water enter in the small forward bilge or does it run along the hull before going into the bilge? If you can see it running along the hull then it must be forward. Also, Seattle – rain, could it be fresh water that gets “salty” as it runs down the inside of the hull from the top deck? Or, it could be the fresh water tank finally springing a small leak. This is easy to check. Drain the tank and see if you still have the leak. You are right there are only a few places where water can intrude. You said, knotmeter thru-hull "drying out the locker it is in (starboard V-berth)" there really should be no wetness in these lockers the starboard one should be as dry as the port locker. The slow leak may somehow be coming in this thru hull.

 

[ish]

I've tasted it, it's definitely salt. Plus *gasp!* it's actually been dry here for two whole weeks, which is what piqued my suspicions in the first place.

The water is accumulating in that odd little pocket in the bilge forward of the mast support step. It trickles into there from the bow, through the little valley between the hull and the liner. You are correct that there is not much more to check... pretty much just beneath the liner forward... or anywhere beneath the water tank, I suppose.

You're right about the V-berth locker, of course... it should be dry if that thru-hull isn't the problem. I have stopped up the drain from that locker and will check in a couple of days; if water accumulates in there and no longer flows into the bilge, I'll have my culprit. But yesterday, even after I had plugged it, new water kept flowing into the bilge but not accumulating in the locker. My theory for why the locker was damp is that it was somehow backflooding through the drain from wherever the actual leak site is. I hope I am wrong, of course, since the thru-hull is a much easier thing to isolate and fix than some random pinhole in the hull somewhere. :cry:

I guess my real question is, if I can absolutely determine it's not that through-hull, is it worth my time and effort to chop up the liner looking for it? And if I don't pull out the liner, how could I determine from the exterior where the water is coming in? Or if I do pull it, will that actually tell me where the exterior leak is (which I must know in order to fix it) or could it be traveling through the glass and emerging at a different spot entirely?

My knowledge of fiberglass integrity is woefully inadequate here.

 

[Paul F]

I have sent a message to Terry Arnold. He has the same boat we do and has done extensive fiberglass work. Maybe he can come into this discussion and give us a clue. I would not get crazy ripping the boat apart until you get a better idea as to what is going on.

 

[jcherubini]

Slow leak possibility.

Ish, I've been thinking of this too and can only come up with one suggestion. The ironic thing is that my biggest pet peeve is rain water, not seawater. I think at times I would welcome a little seawater. These leaking cockpit-seat locker hatches are driving me nuts.

The thing I thought of is the anchor-rode locker. On Diana I have four bulkheads in the v-berth, the chain locker, two dividers under the bunk and the aftermost one (forward bulkhead of head). All my through-hulls (except galley sink) and transducers are in with the holding tank under the aftermost compartment. I made two short longitudinal bulkheads to mount the tank and provided them with drain holes in case they end up holding wet rope or something. Both forward and aft bulkheads of this compartment are sealed up watertight to the underside of the bunktop and fitted with brass drain tubes that can be stoppered with rubber plugs in case a through-hull fails. In a worst-case situation this small compartment can be pumped out with the manual tank-evacuating pump or just left to flood since it will only do so to the bottom of the bunktop. I have not yet proceeded past this but will be fitting additional drain tubes in all the other bulkheads under the bunk.

Some people have provided external drain holes for the anchor-rode locker and may have not sealed the original internal drain properly. If your boat has an external rode-locker drain I will say this is the culprit.

I don't care for an internal rode-locker drain at all. It only adds to smelly water in the boat. My goal for Diana is to provide an external rode-locker drain and vent the top of it as Illingworth did on Myth of Malham (c. 1952). At that time I will have to clean out the bottom of this mucky rode locker and fill and seal it with high-density putty, so that the bottom of it comes level with the new drain hole in the stem. That will get rid of the internal drain hole for good.

 

[ish]

That is an interesting possibility I hadn't considered. The anchor locker does tend to hang on to water for a long time, so it's possible that it continues to leak saltwater into the interior even after prolonged dry spells. Ours has an external drain; I had never considered that this was a retrofit and not the original spec, so I never even looked for an internal drain from that compartment. I've always considered the external drain to be a great feature and have been befuddled with boats that drain to the interior (considering the amount of water that ends up in there!).

I'm going down to the boat today to check the dammed-up locker containing the knotmeter anyway, so I'll pull out the anchor rode while I am there and see if I can find the original drain and check the seal.

Thanks!

 

[ish]

Well, I might be back to looking at the knotmeter thru-hull as the most likely culprit after yesterday's visit to the boat--there was a small amount of water in the starboard V-berth locker. On the other hand, there was also more accumulation in the forward part of the bilge, despite the locker drain having been plugged. The plug, however, was necessarily imperfect as the knotmeter wiring exits through the same hole, so I guess my theory is that had a capillary effect and pulled some water through despite the plug.

This is the area of the bilge I have been talking about; the water comes straight in down that trough from somewhere forward.

And this is the V-berth locker.

The water was pooled below and aft of the knotmeter, although I couldn't feel dampness on the device itself. But it's still a more likely culprit than the hull itself, I guess, and it's an easier fix so I am somewhat relieved. I still have a nagging worry about the volume of water that ended up in the bilge despite the plug, but I can't see any easy way to isolate it any further.

I checked the anchor locker, but either there was never an internal drain there or they did a heck of a job sealing it up, because I can't find any trace whatsoever.

Anyway, thanks to everyone for your help and comments. At this point, I think I will blame the through-hull and plan on addressing it with a haul-out next winter.