Salt water leak under the liner

[Cruiser WannaBe]

I have purchased a 1987 Hunter 34.5' (shoal) and I have a constant leak that makes my bilge pump come on every 4 minutes or so...

I have looked everywhere for signs of leakage, but to no avail. I have hauled it out twice, filled the boat with water up to the liner once, re-caulked 3 through-holes, painted the bottom, replaced my stuffing box, removed all sole boards, and kitchen counter, and I am now ready to start removing sections of the liner. however, i figured I would ask for some help and advice before I proceed...

The water under my liner does not drain well into the bilge, so if anyone has a proven fix for that, I would also like the input (a picture would be great!).

I would greatly appreciate any help!

 

[splax]

Hello,
I too have an '87 34. I am sorry for your pain. I have done much remedial work to mine, which has a fin keel. My thoughts regarding possible sources for your leak are the cockpit drain system, raw water cooling hose, keel bolt(s) loosened, transducer through-hull, head hoses, galley drain hose, lavatory drain hose, anchor locker drain, or a deck seam. Ports are common culprits for water damage, but you describe a leak of some magnitude. That would stress me out incredibly. If your bilge pump comes on every 4 minutes, that's about 45 gallons an hour. Trace the water path from the bilge to the source. Describe any conditions specific to the leak occurring. Good luck.

 

[neild]

I think splax pretty well covered sources.. I solved the water collecting between the hull and the liner by drilling holes ...VERY CAREFULLY..in the bilge this diagram shows it The article was back in 2009

 

[kloudie1]

Another thing to look at is the check valve in the bilge pump discharge hose. If that valve, which is normally right at the bilge pump, has a slow leak, the pump will cycle like that as it pumps water up the hose then stops.. then the water in the hose slowly drains back through the pump, refilling the bilge.. then the pump cycles on again, refilling the hose.. and so on..

 

[Cruiser WannaBe]

Thank you for the quick replies... My shoal model has a very shallow bilge, and I estimate it to be 0.5 to 1 gallon for each time it pumps out, so the leak rate is about 10 gallons per hour.

I have inspected the cockpit drain lines and even replaced one of the hoses as it was very brittle. I closed all through-hull valves to rule out hose leaks. I even tasted the leak water and know it is salt water, and it starts as soon as the boat is placed in the water... I removed all floor boards to find the source, but the liner is very effective in preventing a good diagnostic. The fact that the water between the liner and hull does not drain well into the bilge makes it more difficult to identify the source. I drilled 2 or 3 1.5" or 2" holes on the vertical wall of some liner compartments, in an attempt to see if water was coming from that direction... So far, nothing conclusive.

I am preparing to remove larger sections of the liner, maybe 6" by 12" at the bottom of a compartment, or something like that. I am hesitant in removing sections of the liner because I am not sure how the liner is credited for structural integrity...

If anyone has any experience with cutting the liner or modifying the bilge liner, I would appreciate the help. Neil D, do you know where I can find the article you referenced?

Thank you!

 

[splax]

the article referenced is in the H34 owner mods - http://hunter.sailboatowners.com/in...mid=267&cat_id=31&aid=7118&page=article&mn=34

I didn't understand the purpose of this mod before, and I hope it helps.

 

[Steve Dion]

Shaft Strut?

 

[heart of gold]

What Kloudie said. Your problem sounds exactly what he describes. The Shaft seal is the most probable next source, Is it salt or fresh water, could be the rear water tank.

 

[Cruiser WannaBe]

I have disassembled the check valve and I can also see the water discharge, so I know there is plenty of water leaking in, even if some of the water returns to the bilge. I also know it is Salt water, as I tasted it and I have also drained the water tanks. The shaft seal is dry, and I also just had it replaced, but I guess there could be a leak between the liner and the hull (though unlikely)...

I will have some time in the next week or so to modify my bilge, so the water between the hull and the liner can drain better. I hope I can then identify the source of the leak... My best guess at this time is a through hull... I will try to remove small sections of liner in an attempt to identify the source.

Thank you for all the input! This has puzzled me, so I wanted to make sure I am not missing something... I'll post what I find out.

 

[Guillaume C.]

The liner is indeed an very important aspect of the structure and cutting large holes just to see what lie under is probably not worth messing up the calculation done by M. Steck back then (Yeah yeah, Hunter did put that hole for the table leg right in the transverse beam, stupid thing IMO). Anyway the sections of liner that stand above the hull are the load bearing parts and the section that touch the hull are the loads transition paths and bonded to the hull, so overall there are not that many place where the liner is only cosmetic and can be safely removed.

The only part of liner that I would trim is around the rudder tube. A leak at the base of the tube would be hard to spot and hard to patch at sea because of the liner getting in the way. I have also reinforced the junction between tube & hull... should probably write some Owner's mods when I get time

Some people have reported that the hull and liner was not bonded together at the locations of some thru-hulls, you should probably remove them all to check this possibility. FYI on my H34 the hull and liner are bonded together at all thru-hulls (1985 model)

If water come through the keel bolt, it's entrance should be visible as it is extremely unlikely that there is a gab between hull and liner in those locations.

The shaft strut bolts are another point to consider, but there is no liner at this place so should be easy to see the water coming.

You may also check the engine exhaust hose where it enter and exit the starboard longitudinal "stringer" of the liner. The relatively sharp angle could have damaged that hose (but then it should leak mostly when under engine...)

Have fun, I believe I am "almost" done chasing leaks on mine, almost!

 

[Dan Johnson]

Re: Salt water leak under the liner...

One of the "old school" methods of tracking down a leak is to use baby powder. HUH? Lightly sprinkle powder around thru-hull bases, and at other points where water movement from leakage may be suspected. Water will leave traces in the powder, showing you were water is moving from or to.

Since it starts immediately after the boat is splashed, check around your speedo's transducer mount. Mine is removable and has a plug for when the bottom is painted. I've never removed mine, but each spring I have a small leak from this mounting that lasts about a half day before the O-ring stops letting water past it.

Same thing with the shaft log. After splashing it tends to leak, but after the half hour run to the summer marina, it has stopped. When it hasn't, a slight turn tigher on the packing does the trick.

 

[Cruiser WannaBe]

So I have had some success, but the leak is not yet gone. My bilge pump went from pumping every 4.5 minutes or so to longer periods longer than 1 hr. I cannot tell what exactly did the trick, but I am sure glad it is better...

I tightened the keel bolts, and on two of them I was able to add some sealant in the bolt holes. I contacted Hunter for Keel bolt torques and confirmation that I could remove one keel nut at a time while in the water. They responded I could remove one nut at a time, and the following torque values are applicable:

Keel bolt sizes // Socket size // Torque
3/8" // 9/16" // 21 foot pounds
1/2" // 3/4" // 45 foot pounds
3/4" // 1-1/8" // 132 foot pounds
1" // 1-1/2" // 325 foot pounds
1-1/4" // 1-7/8" // 546 foot pounds

My keel bolts are 1-1/4" so I had to find a 1-7/8" socket, a mighty wrench, and a pneumatic torque wrench. The guy who painted the bottom of my bolt was nice enough to let me borrow some of these tools...

The change in leakage was not immediate, but the leak rate has gradually been decreasing. I just wish I knew exactly what it was...

Other things I have done include (not necessarily in this order):
1) I replaced the bilge pump hoses
2) I drilled a few 1.5" holes on the side of some of the liner compartments in an attempt to track where the leak was coming from
3) I added grooves to the bilge pump liner to better drain the water between the liner and the hull
4) I emptied the fresh water tank in the aft so water would not enter the liner compartment where the rearmost keel nut is located. This would also raise the rudder log some, in case some of the leakage was coming from there.

I wish I had a smoking gun and that I could report that my bilge was bone dry... maybe someday... but for now, I am happy with a much slower leak and I will start reassembling the cabin in the near future.

Thank you all for the input and ideas, and have a Merry Christmas!

 

[hunter healer]

Hi not sure if you are still following the forum, i would like to know where to drill the holes in the bilge. the diagram you added does not read clearly. I see you mention a post from 2009 but where would i find that one? thank you

 

[splax]

Another possibility came to mind. Perhaps a through-hull bond as fractured allowing water to seep in around the flange. Closing the valve would be irrelevant, in that case.

 

[wufibugs]

You said you checked the stuffing box so I assume that when you feel under the shaft there is no water there at all. Water leaking from the shaft not only collects under the engine, but works its way around to the bilge under the liner.

 

[hunter healer]

Thank you, That is what I thought that water may have gotten under the liner and is now positioned aft by the rear keel bolt so when I vacuum up the water under that odd shaped inspection cover in front of the engine cover next to the galley ladder it comes back. So how do I get that water out of there? another strange thing is hull just above the water line where the hull comes to a point at the bow someone drilled a hole through the hull to the other side and I was told that it allows the water to escape the anchor locker. I have never seen anything like this but in this year 83 34.5 model there is an inspection cover under the v berth cushion all the way forward and when I looked in there there was another inspection cut out under that one 14 inches down leading to the hull of the boat? It was a factory cut out that the prior owner stowed stuff in but is that the liner possibly where it begins at the v of the bow?

 

[hunter healer]

I will have to wait till the boat goes in the water in March to check the thru hulls but now I'm trying to the water out of the boat that seems to be between the sole and the liner!

 

[Mark48]

One area not mentioned is where the cockpit drains are glassed to the hull. This has been an issue with some 34s resulting in water coming in while heeling. Same could be true with the exhause system. I didn't have any leakage when not heeled above 15 degrees, but once the drain hole submerged on the heel I had water coming in. Caused the gally floor to rot out. Just another thought. Getting someone to go down into the the lazerette (sp) while heeled was a fun process. Good thing my son-in-law trusts me.

 

[hunter healer]

Hi, great information thank you I would have overlooked the possibility! One question if the sink drain is submerged how would the water get in? Is it poor seal at the connections? I can understand the sink backfilling and then overflowing but the sink is still higher than the high waterline while heeling correct? One other question if I may: hoe would the water come in through the exhaust bc it would seem to me that it would go to the exhaust manifold and into the engine unless there were bad hoses leaking

 

[Mark48]

On some of the H 34s and maybe others the connection of the cockpit drain hoses (scuppers) or exhaust pipe, particularly the cockpit drains, to the hull were not well done and may have some gaps in the glass. You can check while on the hard by a close examination of the exhaust and cockpit drains from the outside of the hull any small crack or holes could be a source of leaking. I think there were some extensive discussions on this issue several years ago. Only leak when under water which is when heeling. In my case to the starboard side.