Leaking Prowler 15 - any more ideas?

   I need help detecting a leak in my Prowler 15.
    It filled with @ 5-10 gallons yesterday on a 9 mile paddle in moderately bouncy swell.  I normally get a cup or two if it's bouncy.
    No obvious cracks seen, so this morning I searched the forum and found this started by Mooch:
http://www.norcalkayakanglers.com/index.php/topic,2932.msg23080.html#msg23080
  Where he said he might try putting newspaper on the garage floor and filling his yak with water.
 First, because I suspected the scupper holes might have a crack, I plugged one side of each and tried to force water into the other side, the looked inside to see if any water has gotten in. None had. 
   So I did the deed, papers on the floor, dried the yak off outside, and filled it until it water was coming out of the center hatch.  I let it sit for a few hours, checking it, especially at the scuppers, but not a drop on the paper anywhere.
  Then, because maybe the water hadn't gotten high enough in the stern, after I bailed most of it out, I tipped it so it filled that end, still no leaks detected. I'm letting it dry inside now, and will probably try it out in the harbor tomorrow to see what happens.
   Other clues to what I hope is your solution:
    I have a 6" center hatch, recently lost the cover, bought a new one that has the twist lock handle that locks it in place, not the threaded lid style of the original.  The ring it fits in had a decent rubber gasket, so I don't think it's leaking under that - unlike some people have reported, I normally don't have water covering the lid - it stays in the footwells.  The lid itself has a small rubber seal, and I could see water might leak in there, but not the amount I had.
    I noticed the front hatch's rubber gasket was pulled away slightly, and one of the defects of the P 15 design was that the lid sits in a moat around the lid that stays full of water, so it could leak in as you tip side to side, but again, I'd be surprised if it would be a large amount of water, but I'm kind of hoping that was the problem.
    There are no openings or drain plugs on the hull of the yak, just on the topsides.
    There is a hole in the plastic at the rear, above the water line, for the rudder pintle, but it is lined with a plastic sleeve.
  Any other suggestions as to where the leak is, and how to find it? 
P.S. I was glad I had a pump attached to the back of my seat back, but I'd always thought I would stick it in the center hatch to pump, but with enough water in the hull, causing water to cover that hatch, that's not a wise choice, so I scooted forward and pumped from the front hatch -something best done before the water rises too much, and I was glad it wasn't any choppier when I needed to do it.   While I was busy thinking of every other reason the kayak would be listing - wave action, wind on my big salmon net, too many salmon sinkers- the boat was quietly filling up! 

1. With the hull dry.....take a water hose and blast it straight at the front hatch for a bit, then check for water in the hull.

2. Repeat step 1 except with center hatch.

3. The boats will flex a bit in a chop....a pinhole might only expose itself when the hull is distorted.  Maybe try throwing a 4x4 under the front and rear then refilling with water, should make it sag in the middle replicating a fexed hull.


If I was a gamblin man I'd bet 1 or 2 though.

An easy way to detect a leak is to take a shop vac with the small blower attachment. Open the drain plug and presurize the hull a little and walk round with a spray bottle with dish soap in it and spay the hull, hatches ,ETC. You will find th leak quick with bubbles coming from it...its the same method gas companies use for detecting gas leaks. Its quick and easyand has work many of times before.

My initial guess would be the center hatch... I'll never use another yak with one of those.  Quick check is to stream water over it from different angles & seeing if any makes it into hull.

I'd check the front hatch - when the straps are dry they may seem tight, but when they get wet they can stretch and the front  hatch can then be loose.  Sloppy, pounding waves over the bow can then lead to water inside.

I ditto Harold on the center hatch. I bought a scupper that had one already installed and that damn thing always leaked................ I like Abdivers idea the best. That will definelty show where the hull is compromised. Were you constantly taking water over the top on your paddle? 5-10 gallons is a shitload of water.

What I would do is turn it over in the darkened garage and put a shop light inside the hull, focusing on areas where your weight would flex the plastic.  A crack may only be apparent under stress, as others mentioned, but a shoplight will turn that sucker into a big lamp.

That's a lot of water!

What I would do is turn it over in the darkened garage and put a shop light inside the hull, focusing on areas where your weight would flex the plastic.  A crack may only be apparent under stress, as others mentioned, but a shoplight will turn that sucker into a big lamp.
That's a lot of water!

+1

Thanks guys, for giving me something else to try.  I'll try the shoplight thing tonight.  Then the squirt the hatch, then the shop vac when I locate one. 
  FYI, I took a couple of boat wakes over the nose, but that's it, it was a little bouncy, and the front hatch is always wet from paddle water.  I think the idea that it was flexing open makes sense - I have always gotten a cup or two more in there when it's bouncy.

Had a P13 that began taking on quite a bit of water no matter where we went.
Don't have any idea how it happened but it ended up getting a pin hole on the side of the bow. Literally looked like it was stuck with a needle.
The shop light trick was how I found it.
Hope it's something very minor.
You also might want to smear some goop over the screws on your pad eyes, especially if any of them are near the water line.

My initial guess would be the center hatch... I'll never use another yak with one of those.  Quick check is to stream water over it from different angles & seeing if any makes it into hull.

I'm with Fuzz on this one. I have a p15 but I purposely bought the one with no center hatch because I'm a big dude at 250#. Glad I didn't too because that thing is right at the waterline with me and my gear in the boat.

It has been a very dry boat for me that takes on maybe a tablespoon of water after a long day. I have noticed that it is much more flexible in the swell than any of my previous boats. Nothing bad has come from it but it is a bit disconcerting to feel your boat twisting and flexing as it goes over a swell or wind chop.

Let us know what you find! Really curious to know the culprit.


-Eliot

1. What we have here is a failure to Goop!
2. Just because the new hatch ring comes with a gasket doesn't mean it will make a good seal.
3. The large hatch straps have to be really tight, or they let in enough water to make the yak sit low enough in the water to cover the small hatch with water, and then the small hatch leaks.
4. And it could be something else as well, but I'm pretty sure the "usual suspects", the scupper holes are sound, now that I checked them every way I could.

But damn, have I got a clean kayak now!  36 gallons of water inside yesterday, no leaks(but I didn't get the water inside above the 6"hatch ring).
Today, the shop vac blower thing and soapy water (Ivory, glycerine, kids bubbles) all over the yak.
I didn't have a nozzle small enough for the drain plug and cut some foam to wedge the hose into the small hatch.
  You can see by the pics that the only places I got bubbles were at the sort of loose fitting drain plug (but high enough above the water I don't think it gets more than a few drops in that way, though I'll put some plumbers tape on it anyway), and around the new hatch ring I installed because I couldn't get a replacement screw in hatch cover like the one I lost on the highway.  And did that repair just before this scary amount of water got inside.
   I thought about Gooping it, but I don't normally get much water standing on top of the small hatch, and honestly thought the gasket was thick and flexible enough to keep out water.  Ocean Kayak should know better!
    The air really blew out strongly from under the ring. 
    I still don't know if the actual hatch cover's internal gasket is sufficient to prevent water seeping in, I might try rigging something up to blow into the drain plug hole to test it. But I can open the new one easier than the old to check to see if I'm taking on water.
   The shop light trick was useful in the areas I could reach, but I couldn't get it to the stern very well, took the guard off it and taped it to a pole and did the best I could.  Scary to see all the wavy lines it shows up- almost looked like cracks, but I'm pretty sure they're just thinner and thicker areas of plastic.  A couple of areas that were surprisingly thin and let a lot of light out: the skid areas on the bow and stern, but no holes - yet, tho I think I'll try hot glue lines or Gooping a skid plate at least on the stern, so I don't get leaks with more wear.
    The large hatch straps, that I thought were tight, needed more tightening to keep the air from blowing out, but tho it probably will still leak a little there, the water that sits in the "moat" isn't under pressure - it probably just wicks in slowly.
   I'll keep you posted after I goop the hatch gasket and give it test ride- in the harbor, with a 5 gallon jug of water  in the tank well in place of my gear and the big fish I plan to catch as soon as I'm done wasting September on this project.
   Maybe this post should be cross referenced in the Safety First and/or Choosing a Kayak forums. Seriously.

     

Glad you found/verified the source.

IMO, the center hatches are just leaks waiting to happen.  Any substantial weight on yak & there's always water on/around the center hatch.  They may work fine when new... but rubber gaskets age & lose flexibility, rivets leak, o-rings get sand on em, hulls flex/warp, etc.  Too many potential points of failure for something that is surrounded/covered with water when kayak is on full load... and/or water sloshes back & forth over in choppy seas.

I am glad the shop vac trick was usefull and that you were able to find the culprit. Soapy water for finding leaks is cheap and a extremely effective tool.

probably not your problem, but I have seen lots of water come in from flush mount rod holders when the cap on the bottom is either gone or cracked.