Transom bung drain

[mikeyoboy]

I want to install a drain bung in the transom of my Tornado 5.3m as fully sealed and water sloshing inside. Question is how high / low do I cut the whole to not catch the keel and also how to ensure the ply within the transom is sealed so it does not rot? I’ll be using a 25mm drill bit but conscious the transom is almost 2” thick and I don’t really want to create too large a hole to have to gelcoat inside it. Any thoughts appreciated!

[charliee]

Maybe add another bilge pump?

[Poly]

Originally Posted by charliee

Maybe add another bilge pump?

I don’t think you’ve understood the question, or design concept that the tornado (and many other ribs) have.

[Poly]

Originally Posted by mikeyoboy

I want to install a drain bung in the transom of my Tornado 5.3m as fully sealed and water sloshing inside. Question is how high / low do I cut the whole to not catch the keel and also how to ensure the ply within the transom is sealed so it does not rot? I’ll be using a 25mm drill bit but conscious the transom is almost 2” thick and I don’t really want to create too large a hole to have to gelcoat inside it. Any thoughts appreciated!

Unless anyone has direct experience (perhaps drop Kraken a pm as he used to build tornados) then I think you’ll be little bit trial and error. I’d say you have two choices: 1. Drill a small hole in the transom at your best guess position and then use that to feel if you got it right and then enlarge in whichever direction is needed.
2. Drill a small hole in the deck near the transom and measure the distance inside, transfer the measurement outside and drill accordingly; then plug the deck hole.

Either way, you will need to properly seal the holes, and I’d suggest you want to trace the source of the leak - there is no bung as the design intended it to be water tight.

[charliee]

Quote:
Originally Posted by charliee View Post
Maybe add another bilge pump?

I don’t think you’ve understood the question, or design concept that the tornado (and many other ribs) have.

Poly, I was quite aware of the design, but clearly there is a leak - with that in mind you could cut a hole in the deck and install a bilge pump and cap off with a small inspection cover. Presumably Mikeyoboy can't find the leak so the boat will probably keep filling up when left in the water - a drain plug will only be useful when the boat is out of the water and as boats are designed to live on the water it might be an idea to keep extracting the water as it fills.

[Poly]

Originally Posted by charliee

Quote:
Originally Posted by charliee View Post
Maybe add another bilge pump?

I don’t think you’ve understood the question, or design concept that the tornado (and many other ribs) have.

Poly, I was quite aware of the design, but clearly there is a leak - with that in mind you could cut a hole in the deck and install a bilge pump and cap off with a small inspection cover. Presumably Mikeyoboy can't find the leak so the boat will probably keep filling up when left in the water - a drain plug will only be useful when the boat is out of the water and as boats are designed to live on the water it might be an idea to keep extracting the water as it fills.

Putting a bilge pump in a hull that was designed to be water tight is a bodge. To do it you have to put wiring in, plumbing out, inspection hatches, all of which are more sources for water ingress. Fixing the leak is the correct solution. A bung to keep an eye of the issue and drain any water until it is resolved is a sensible solution.

[jeffstevens763@g]

this might help for position of the hole

Tornado 5.3M Pattern PVC Tube
if it were me
gorilla glue is 100% waterproof and swells 4-5 times i would cut the hole clean the ply, seal with epoxy resin fit your bung assembly with the gorilla glue. the surface on one has to be wet to activate the glue tape around the area so spillage dosnt mark the gel-coat

[mickter]

try cutting oversize hole, fill and drill right size hole in filler. that way you can`t get water in wood.

[jeffstevens763@g]

Filler won't soak into the wood and leave a construction joint where water will soak into, you could also use a product called swell seal mastic does as it says but you need to treat the wood

[mikeyoboy]

Bilge pump will only take from within the working area of the boat not within the hull. The 5.3m also doesn’t have a scoop for a bilge to sit, has an elephants tail to dispose of water under momentum. To install a bilge within the hull is major work and I reckon the water is a build up from years of sitting without use

[mikeyoboy]

Originally Posted by Poly

I don’t think you’ve understood the question, or design concept that the tornado (and many other ribs) have.

Agreed. Some good ideas here though

[mikeyoboy]

So the hull has been sitting for c.10 years and I’m about to replace the tubes. As part of this I’ll be redoing gelcoat to underside and buffing top which just needs some tlc. As I’m picking up on Thursday I need to drill a hole to release the build up of water in the hull and it can drain en route home.

I’ll be doing a proper restore on this rib as I really like Tornado’s and we’ll pleased to have sourced.

As rightly pointed out, there’s a leak which I’ll get to the bottom of but in the interim I want to ensure I do each element correctly starting with drilling the transom. I wouldn’t be so worried about cutting the hull as glass fibre but as this has a ply sandwich I want to do right.

Thanks for feedback, very useful!

[telcowilliam]

I have a 5.8 tornado which has an under deck drain plug, I have also added an above deck drain plug myself, under deck water comes in through front anchor locker, I only take the bing out every now and again. I take the above deck bung out when leaving the boat on trailer as the elephants trunk is a little high for rainwater to flow out of. I have also fitted a bulge pump in the back well of the boat to remove water when required. Sorry I don’t have any pictures but could get one tomorrow

[mikeyoboy]

I would have given my eye teeth for a 5.8, but this came up and it’ll be perfect for my needs. This all makes sense but unfortunately I don’t have an anchor locker or a well. Flat working platform to rear. They even put a well in the later 4m probably based on feedback. This will be its first hull bung. I think I’ll oversize marginally and cost to protect the ply in transom and reseal around stainless bung which just arrived.

[mikeyoboy]

Transom without drain...

[jeffstevens763@g]

Don't forget about condensation over that period of time too

[mikeyoboy]

That’s a worry but they’re pretty tough ribs. Will see when I start to drill on Thursday [emoji30]

[jeffstevens763@g]

Originally Posted by mikeyoboy

That’s a worry but they’re pretty tough ribs. Will see when I start to drill on Thursday [emoji30]

you could drill 2mm holes in a line to find the end of the transom wood for more presion.

[cgoing]

Originally Posted by mikeyoboy

Attachment 126484
Transom without drain...

Just retubed a Tornado and the lower cavity drain on this one is installed in the well in front of the transom. [ATTACH]126501

[mikeyoboy]

I don’t have that privilege. Flat Work area on deck with no rear well to front of transom to drain to, only trunk. Hull completely sealed yet I can hear water inside. Anyway, bung recess being cut tomorrow afternoon to initially drain, then seal and install a stainless captive bung. Gulp!