Fibreglass Hull Leaking

[bushonion]

G'day everyone,
My fibreglass runabout has been out of the water for a few years and went back into the water this week. When I opened the bung a few liters of pretty rusty looking water came out... She's never had a leak before and I don't know we here to start.
Any advice welcome...I'm scared of the possible implications/costs/getting ripped off if I take it to a repairer which I will have to do because I am not technical/strong/equipped to fix it (just an old grrl who likes to fish)
Cheers

[fat-buoy]

I had a tinny which used to take on water.. and after agonising about the possibility of a hole etc I decided to check the bung a little. What I did was to put a lick of silicone around the bung backing plate (female component attached to the boat) and then put a lick of vaseline around the thread of the actual bung... The next trip when I opened the bung not a single drop came out so I guess it was just a bit of water either getting past the thread and seal or behind the bung itself.

Worth a try before putting extra $$ into it.. PS I was told that the vaseline would deteriorate the bung plastic and it may well have but I had the boat for over 4 years and didn't notice anything at all different and worse case scenario is pay $10 some time down the track to replace it.

[fat-buoy]

I had a tinny which used to take on water.. and after agonising about the possibility of a hole etc I decided to check the bung a little. What I did was to put a lick of silicone around the bung backing plate (female component attached to the boat) and then put a lick of vaseline around the thread of the actual bung... The next trip when I opened the bung not a single drop came out so I guess it was just a bit of water either getting past the thread and seal or behind the bung itself.

Worth a try before putting extra $$ into it.. PS I was told that the vaseline would deteriorate the bung plastic and it may well have but I had the boat for over 4 years and didn't notice anything at all different and worse case scenario is pay $10 some time down the track to replace it.
That is weird... when I read my post it says I decided decided (why I would decide twice is beyond me) but when I go to edit the post I have not written the word "decided" twice at all???

[thump-a]

Put your bungs in and fill the hull with water. See if you notice any water leaking.

Easiest way to find na leak

Cheers

[bushonion]

Thanks Fat-buoy,
I did put a new bung in yesterday thinking that might have been the problem but have not taken out the bung plate and will look to see if I can do that.
The top bung (which drains the above floor part) isn't taking water....

[bushonion]

Put your bungs in and fill the hull with water. See if you notice any water leaking.

Easiest way to find na leak

Cheers

g'day Thumpa...
And thankyou The leak is UNDER the floor - no access from above/outside except through the bunghole...so to do what youre suggesting, I would have to put water in then close the bung - Is that wise?

[Jackinthebox]

Sounds like your only option, unless you have an access spinout in the floor somewhere?

Not too much water or you might damage your trailer (and boat if it is on hull rollers :)

Maybe just a couple of inches at first.

Cheers,

Mick.

[bushonion]

Thanks... There is no other access.

[finga]

Was the boat stored outside under a tarp or with no cover?
Is it under a tree or was there a lot of leaves in the boat?
Was the boat stored with the bungs in?
If the bungs were out when stored was the rear of the boat 'downhill' from the front to a fair degree?

If it was new water coming in it would not be all rusty in colour I would have thought.
Filling the hull is not the only way to find a leak and pending on where you are I might be able to help.
I made a gizmo that pressurizes the hull to one or two PSI so you can spray soapy water about and look for the bubbles.
A hull full of water weights a hell of a lot.

[tropicrows]

Lower the trailer at the front so the boats bum is in the air. Put the garden hose in the bung hole and add 20 to 40 liters, now add some food coloring. Put the bung in mix the water with the food coloring, then re level trailer and watch.

[propdinger]

sounds like old water from storage to me. trapped in hull till you used it seen this many times of boats that sit for ages

[Jarrah Jack]

Was it fresh or salt water? Before you put water in the boat resilicone the female part of the bung where its screwed into the hull then put the bung in tight with some vaso on it and go for a run in the boat and see if there is any water coming in.

Second step should be the colored water if its still leaking.

[bushonion]

Is it under a tree or was there a lot of leaves in the boat?
It was for a period and yes a lot of leaf litter and water had accumulated - drained
and cleared/washed....but that's in the open section of the boat - above the floor
as you'd expect from rain etc. The water that worries me is below the floor.

Was the boat stored with the bungs in?
Ditto but not for the last 3 months

If the bungs were out when stored was the rear of the boat 'downhill' from the front to a fair degree?
Bum downhill but not greatly

If it was new water coming in it would not be all rusty in colour I would have thought.
Yes I agree...though it may have been a mix of Swan river water and rust from
the bung hole thingy itself...the second days run was not as rusty as the first day's
run

[I]Filling the hull is not the only way to find a leak and pending on where you are I might be able to help. I made a gizmo that pressurizes the hull to one or two PSI so you can spray soapy water about and look for the bubbles.
Sounds brilliant. I am in WA (Mt Lawley)

A hull full of water weights a hell of a lot.
Yes that worries me I'd have to say

Cheers

[bushonion]

Tropicrows, Jarrah Jack and Propdinger,

Didn't dare taste to tell if it was fresh or salt to be honest!

Many thanks - will reseal the bung thingy and take it for a run then try the other ideas.

Heaps of thanks all!!

[WalrusLike]

If its old water it will only be a trickle next time or will be none at all.

I would trailer it to a steep hill with the bungs in then open them. If no water then I would take to ramp put in for 10 minutes and pull out.

If water comes out of bungs then you know it's a leak and you need to investigate.

[bushonion]

This might seem like a dumb question (sorry)... but if the hull is sealed with the only access being the bung-hole, how would water get into it while it's sitting on the trailer?

[Dennis@twdfibre]

Do not under any circumstances put the hose in the bottom bung and fill the under floor area with water, you will force water into areas that cant drain out. The water you got out of the boat was most likely condensation that built up over a period of time. When not in use you should undo the bottom bung and put the nose of the boat up. There are only 3 ways water can get in the under compartment. 1 through a badly sealed drain bung, 2 through a crack/ split of damage to the underside of the hull, this you shoud be able to see and 3 through a crack/ split in the floor this you should also see.
Have you used the boat again, did you get water out of the bottom bung.

[tropicrows]

If the boat was built properly at the factory no harm will come from putting water to the lower hull area. You are not filling the hull, your only putting an enough in to check for holes/cracks along the keel line. I suspect it's more than likely small cracks around the the floor edges, which can also be checked by putting some colored water on the deck area and waiting to see if any comes out the lower bung hole.
I have seen water put into a hull many times and done it myself once or twice. If the under floor section has timber in it and it has not been sealed correctly during manufacture then it's most likely already rotting out so a bit more water wont do any harm. You could also add some water soluble anti fungi solution to the water to help stop any rot that may have started but can't be seen.

[CT]

If your worried about pumping in water under the floor and the rot implications, use antifreeze (ethylene glycol). It kills rot and is a pretty green colour so no need for the added food colouring. Don't lick you fingers!

Cheers
Craig

[bushonion]

New bungs in, silastic replaced on transducer and speedo...took her for a good solid belt up the river...... and she's watertight!

Thanks everyone - brilliant support!
:-) on to the next challenge...

[STUIE63]

Thanks for coming back and telling us how you went and it is good news that the leak is fixed