1984 Hunter 31 - Persistent leak near fuel tank

Jul 29, 2016
55
Hunter 31 Comox BC
Just bought a 1984 Hunter 31. Spent a week now throwing 8 garbage bags of junk from the boat, two days of hull cleaning and locker emptying and cleaning and now starting massive interior cleanup. Found after raining 5 of the ports leak, but thats ok, I know where the leak is and what needs to be done.
Its water in the back of the quarterberth that keeps showing up. I cant put the matteress back in until its found.
Fixed a leak in the port side cockpit drain piping, thought I had found and fixed the problem. Then after cleaning it up, noticed water back again seeping under the plywood wall between the berth and the fuel tank side to the left of the rudder.
We have had the panel below the binnacle off and its OK there, no water (except for water from the port locker drain hole! Poured out from the binnacle access when we tested it to see where it went)
We have been inside the fuel tank side best we can, found water on top of the fuel tank!, with no idea or indication where it was coming from, all the lines and hoses we can get to are dry, its a mystery. The plywood above is dry. We need to find it. The plywood wall is coming out tomorrow so we have better access and maybe we can find it.
We have been cleaning the cockpit area so I know its coming from that water, but will also come in rain as well which we get plenty of in the winter.
Anyone have a similar problem or have any ideas??
 

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Mar 20, 2011
623
Hunter 31_83-87 New Orleans
Port side locker drain hole - this storage area from cockpit should be all glassed in with the drain hole running into the cockpit. Suggest checking port/starboard scuppers for leaks around the drains themselves. Check around pedestal mount for cracks in sealant. I had water from there until resealed. For starboard area near fuel tank, check manual bilge hose run and the exhaust hoses. Where is your freshwater pump located? is it mounted on the other side of the wall in the starboard storage area?
 
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SFS

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Aug 18, 2015
2,065
Currently Boatless Okinawa
Glad to see this thread, as we are battling the same leak. Please keep posting as solutions are found or potential sources are eliminated. Here is what I know so far, and the 5 days of rain from Hermine helped us troubleshoot:
1) I rebedded the port cockpit scupper ahead of the storm. That source of water has now been eliminated. I thought that was the entire problem. My theory was that the water I kept finding amidships at the bottom of the plywood wall (now delaminating badly) was simply traveling from further forward, across the quarterberth surface, until it got to the plywood wall and moved under it, spilling off the edge on starboard side of the wall. Not the case (see #2 below). However, rebedding that scupper did seem to lessen the amount of water pooling on the top side of the false ceiling above the quarterberth (the panel you said you removed, under the binnacle), so there are fewer drips now though old fastener holes onto the quarterberth.
2) I am beginning to suspect the binnacle base, as there is still a relatively large amount amount of water pooling on top of that false ceiling previously discussed, but it pools further aft, and more to starboard, of the binnacle. The pool of water is visible along the starboard edge of that false ceiling - you can see it if you climb in the well under the starboard lazerrette. For the duration of the storm, we rolled up a long dishtowel, put 1/3 of its length on top of that false ceiling in the pool of water, and hung the rest into a 5-gallon bucket as a wick to pull the moisture into the bucket. It worked well. Otherwise, the water would have ended up in two places: The deepest well just behind the battery tray, and the quarterberth surface under the plywood wall.
3) Tomorrow I will have a camera arrive that will help me look around in those tight spaces, and will continue to post ideas. I've also sent you a private message. To open it, click on the envelope icon at the top right of this page, next to your screen name.

@jmce1587 - When you speak of the "port side locker drain hole", can you be more specific? Do you mean the shallow lazerrette on the port side of the cockpit, that runs fore and aft, or do you mean the port side of the aft lazerette? In either case, where is the drain hole you mention?

Also, what sealant did you use to reseal the base of the pedestal mount? Did you simply reseal, or did you remove the pedestal and rebed everything?
 
Mar 20, 2011
623
Hunter 31_83-87 New Orleans
Hi. For the pedestal I removed old caulk aruond and recaulked with boat life caulk.

Yes the port side locker is the shallow one with access from the cockpit that runs fore and aft. Inside towards right rear towards cockpit side there is a drain hole that empties into the cockpit. If you have any cracks in this fiberglass compartment then they may be draining into your port side lazerette. Unfortunately overseas at the moment and won't be back for a few weeks. I will check my pic library to see if I have any of this area. If not will Send when I get back.
 
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Oct 24, 2010
2,405
Hunter 30 Everett, WA
One trick I learned to find water leaks (may or may not work in your case.)
Connect a shop vac to blow (hook the hose to the air output like you would do to blow up an air mattress) and secure it to the boat in such a manner as to pressurize the inside of the boat. Close all hatches and the companionway. duct tape any obvious holes. Pressurize the hull and chase the leaks from the outside with a spray bottle of soapy water. Bubbles = a leak.

Best of luck
Ken
 
Jul 29, 2016
55
Hunter 31 Comox BC
OK update time.
Thought we had it fixed when we found the port scupper leak, felt good!
Then after more boat washing we found water coming under the plywood wall between the berth and the fuel tank.
Anyway after an awesome sail today (was too nice to work on the boat) we had to it after dinner until dark.
We finally found the problem.
When water gets in the starboard aft lazarette near the transom, it gets through a crappy seal where the fuel tank vent and overflow hoses run through the floor.
The water then runs down the black vent hose and then lands on top of the fuel tank. It flows over the starboard side of the tank eventually and then down the side then underneath and comes out under the plywood wall.
It also sits where the wires are for the fuel gauge on top of the tank ( previous owners had made a little dam around the gauge to try and stop the water, what a joke - Just find the damn leak) No wonder the gauge doesn't work!
Water could get in from a big storm or in our case lots of washing with a garden hose. We had an immense amount to do as the boat hadn't been cleaned for a few years.
It was hard getting the plywood wall out as it was jammed, but some pounding with a hand had it out in no time.
We are going to cut the wall in two pieces forward of the fuel tank, but aft of any filters mounted to the wall. Reason for this, ease of accessing the rear scupper and other tubing and fuel tank without having to remove the filters mounted on the wall.
Will join the two with a 6" x 1" piece of wood for rigidity.
Now the port lazarette drain. It has a small hole and we were wondering where it drains as there is no hole in the cockpit.
It drains into the ceiling below the binnacle mount! Water then rolls around in there and also drip down into the false ceiling below.
Guess they presume it wont be much and it will evaporate! I am going to have a very close look and see if a drain hole may have been in the cockpit but has been sealed shut.
However we had a small crack in the lowest point allowing drips down into the battery well.
Plugged the lazarette drain, as its not needed.
So all leaks found and when we are finished dry!
Suggest sealer under the lazarette tops as well, to help keep any water out.
 

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Jul 29, 2016
55
Hunter 31 Comox BC
In regards to the pedestal mount, we didn't have to do anything at least for now, we did a good garden hose test and it was bone dry, no water coming in there. Also extensive testing on both cockpit scuppers, both bone dry now.
Yes, I meant the port lazarette and the small drain hole in the aft end of the lazarette.
 
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SFS

.
Aug 18, 2015
2,065
Currently Boatless Okinawa
Glenn, Great pictures and hugely helpful post. We will start on this today, and I will post my findings as well. My one concern is that unless I have been completely unobservant, my port laz does not have the drain you speak of.

Can you elaborate on how you think the water is getting into the aft laz in the first place? My molded channels between the coaming and the lip for the laz seem to drain pretty well due to slope - the water slides along the channel aft of the seat tops, turns forward at each coaming, and slides off the front of the laz onto the cockpit floor, very close to each scupper. I have been aware for some time that I can spray water from a hose, parallel to the transom, directly into that channel with the seat top closed, and the water will swirl up the sides of the channel, be forced under the lip of the seat, and over the forward lip of the channel to be redirected into the laz, but I always thought that problem was due to the relatively high pressure of the water coming out of the hose. Would rainwater and/or sheet flow coming off the coamings provide enough pressure to force water up over that lip?

If so, any ideas on some sort of seal to prevent that avenue of water ingress? I do agree that there is often water in the aft laz, as very frequently the lines I remove from starboard side of that laz feel damp.

Also, how are you going to reseal the holes in the laz floor where the two hoses go through?
 
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Jul 29, 2016
55
Hunter 31 Comox BC
Normally, water would not get in. However a good storm, hosing down to clean would get some to splash in above the grooves behind the lazarette. We didnt put much water in there to clean it when we did, we used just enough to clean and the toweled it dry, but it didnt take much to find that spot and leak down. Once down it will eventually make its way down the back of the fuel tank and then under it and to the plywood wall.
It may not happen until you get it out sailing and heeling over, getting water on top of the tank to move and slide over the edge.
We are going to put a sealer in between each rubber stopper along the edges of the lazarette to try and keep any water out. We will use that stuff that comes in a roll and you just stick on.
We are going to dig all the old sealant out and let it dry, and right now not sure which sealant we will use, will have to check at the local marine store to see what they recommend.
I may replace the black vent pipe because as you can see in the pic, its stained white from leaking over a very long time.
Am very happy we figured this out.
Its one of those leaks that water gets in and nothing happens, then once the boat moves, the water moves and then it starts to migrate to the wall. Sometimes so little gets down it may just evaporate sitting on top of the fuel tank. If your fuel gauge isnt working good chance its because of this.
Sealant is great to prevent leaks, its not meant to patch things up to stop allowing water from leaks to migrate from one spot to another as the previous owner had done, take the time to track it down and fix it.
Now to fix 5 of the 7 ports that leak, but at least its easy to see where the leak is, unlike this other mystery leak!
This poor boat had been so neglected, she is getting a new lease on life, once done with this immediate stuff a complete interior detail and clean.
 
Jul 29, 2016
55
Hunter 31 Comox BC
The port lazarette should have a very small hole at the bottom left front corner as you look at the lazarette from the cockpit. There is a circular depression in the lazarette floor there, and its just in front of that. Not sure what the circular depression is for, seems kind of useless.
 
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SFS

.
Aug 18, 2015
2,065
Currently Boatless Okinawa
Ok, here's what we know from our work today:

1) I have no water, nor any sign of there ever having been water, on top of the fuel tank. We don't have a fuel gauge. This is really disappointing in a way, as I thought we had a real lead. However, I will still investigate whether we are getting water through the floor of the aft laz. With so much of the boat in disarray because the soles are out, we didn't want to empty that aft laz and start looking at things,as there was really no place to put the gear.

2) We have a large number of fasteners driven into the coaming all the way around the cockpit that appear to have no purpose. Perhaps at one time there was a cockpit enclosure of a different type than the one we have now, which uses a sort of snap head fitting. In any event, they all need to be removed and either wrapped in butyl and put back in for appearance sake, or taken out and the holes filled with thickened epoxy. I found 3 fastener holes in this mix that had no fasteners in them. Holes don't appear to go through, but I taped them over until I decide on epoxy or not.

3) One of the bimini fittings on the coaming was extremely loose. Tightening the screws helped on one side, but the other was stripped completely. As a temporary fix, I took the fitting out, bedded it with butyl, and put it in with one fastener. Would have epoxied it immediately, but had to move on to other epoxy hotcoats elsewhere, and we are expecting thunderstorms this afternoon. Will properly rebed all 4 bimini footings ASAP.

5) The drain in the port lazerette has been badly patched, and is likely a culprit regarding the water over the quarter berth. The exit hole on the vertical wall of the lazerette has been patched with epoxy (and I never noticed the patch in all this time), and the entrance hole inside the lazerette has a portion of what looks like a straw caulked in place, then caulked shut. I will attempt to rip that out, and either run a new drain, or epoxy the interior hole closed properly. I wish I could look up from the quarterberth and see the shape of the molded laz shelf and its walls.

More updates as I learn more. Thanks again for your help.
 
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Jul 29, 2016
55
Hunter 31 Comox BC
Really check that seal where the two hoses go through the floor of the Lazarette though. Have someone pour some water right on the seal and be below and see if you can see anything, however you cant do this until you remove the wall. Keep in mind there may not always be water there, as its an occasional thing and then gets swished around when heeled sailing. Need to watch and test with a garden hose.
Still going to monitor, because there is always a chance water could be coming from somewhere else, but was dry this morning after rain last night.
If water is getting in through the sealer by the vent pipes, it may not show up on the fuel tank as your setup may be a little different than mine and it would miss the top.
I was relieved to see the scupper exit was dry once we removed the wall.
I also noticed the chrome posts in front of the pedestal are loose, however I don't see then attached above that false ceiling, but I may loosen clean and reseal just to be safe.
We don't have a bimini yet, and there are no other attachments really.
I had a close look for an exit hole for the port lazarette drain but I couldn't see anything. It could have been a good epoxy job covered in paint. It sure drained well from the lazarette though!! right onto the ceiling!
We had a small crack on the starboard edge of the ceiling and small drips were going into the battery storage area on that side. Explained where that was coming from.
 
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Jul 29, 2016
55
Hunter 31 Comox BC
Port side locker drain hole - this storage area from cockpit should be all glassed in with the drain hole running into the cockpit. Suggest checking port/starboard scuppers for leaks around the drains themselves. Check around pedestal mount for cracks in sealant. I had water from there until resealed. For starboard area near fuel tank, check manual bilge hose run and the exhaust hoses. Where is your freshwater pump located? is it mounted on the other side of the wall in the starboard storage area?
No leaks on either scupper, no leaks around pedestal. Freshwater pump is in the starboard storage area.
 

SFS

.
Aug 18, 2015
2,065
Currently Boatless Okinawa
My binnacle sits inside a pedestal that is molded into the cockpit floor. There are no seams at the cockpit floor. It could leak at the outer edge of the circular base that is inset into the pedestal, but it looks like that has been painted over, as have the edges of the fasteners. I can find no cracks, so I'm going to move on to other things in my search.

We discovered a crack on the starboard edge of our ceiling also, that drips a small amount of water onto the hot water heater. I'll be epoxying that.
 

pateco

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Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
Really check that seal where the two hoses go through the floor of the Lazarette though. Have someone pour some water right on the seal and be below and see if you can see anything, however you cant do this until you remove the wall. Keep in mind there may not always be water there, as its an occasional thing and then gets swished around when heeled sailing. Need to watch and test with a garden hose.
Still going to monitor, because there is always a chance water could be coming from somewhere else, but was dry this morning after rain last night.
If water is getting in through the sealer by the vent pipes, it may not show up on the fuel tank as your setup may be a little different than mine and it would miss the top.
I was relieved to see the scupper exit was dry once we removed the wall.
I also noticed the chrome posts in front of the pedestal are loose, however I don't see then attached above that false ceiling, but I may loosen clean and reseal just to be safe.
We don't have a bimini yet, and there are no other attachments really.
I had a close look for an exit hole for the port lazarette drain but I couldn't see anything. It could have been a good epoxy job covered in paint. It sure drained well from the lazarette though!! right onto the ceiling!
We had a small crack on the starboard edge of the ceiling and small drips were going into the battery storage area on that side. Explained where that was coming from.
My fuel and water hoses do not go through the lazzerette. Fuel is aft of the starboard cheek block by the rail, and fresh water has the fill port actually mounted inside the lazzerette so no hose. (took me a few days of cleaning things out to find that one.)
 

SFS

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Aug 18, 2015
2,065
Currently Boatless Okinawa
Chip, I'm working from memory, but of the two hoses we are talking about, one is a fuel vent hose, and the other is a vent for my water tank. There are two other larger hoses that pass though my laz floor - both the intake and the discharge hoses for my manual bilge pump.

And it took me a while to find my water fill also. That fitting will need to be checked for leaks as well while I am looking around.
 

pateco

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Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
one is a fuel vent hose, and the other is a vent for my water tank.
Both of my vents exit the stern on the starboard side and do not run through the lazarette, but behind it.

2014-12-27 16.03.03.jpg
 

SFS

.
Aug 18, 2015
2,065
Currently Boatless Okinawa
@pateco My vents are in the same position as yours. Wait, BEHIND the laz?? On my boat, the inside of the transom wall IS the back of the laz, there is nothing to get behind. So the hoses come up through the floor of the laz and turn aft, then connect to their fittings.

That is weird. Does your laz have an aft bulkhead or something? I see another difference. You don't have a discharge for your manual bilge pump on the transom. In fact, I don't see an attachment point for the handle of a bilge pump on the starboard side of your aft cockpit coaming. Where is your manual bilge pump?

Who would have thought there were such variations in the same model year boat (although I guess the PO could have moved my pump or yours).
 
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Jul 29, 2016
55
Hunter 31 Comox BC
The back of the Lazarette is the transom on mine too. Mine in the same location on the exterior on the transom however. Making room to have them not go through the lazarette floor and naking room behind makes total sense. Was thinking if doing that initially, but there are no options to do it.
 
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