Boat builders never think about afterwards.

[mocruising]

Just had the sad news confirmed that my ss steel water tanks are leaking. The boat was built in 1997 so I feel this is premature. We discovered that it (They) were leaking at the end of last season. There are two tanks joined by a single pipe and filler fitted under the cabin sole. We had hoped that the problem was with the joining pipe, which was renewd and replaced but it has now been confirmed that both tanks are leaking. How two lots of corrosion presumably on the welds manifest them selves at the same time after 14 years beats me.

The problems now start. Removing them is bad enough but they wont go up through the companionway so have to be cut up down below and how to get the new ones in. Will have to make them smaller I suppose and have three tanks instead of two, all joined together. You are talking 1000 L here.

The cause I guess is some thing to do with the hard water we have been taking on board in Greece and throughout the Med over the past 8 years.

I am lucky I am still working and able to throw money at the problem to make it go away. I don't suppose I will get much change out of 4,000 in the end.

Any one else faced this problem with a boat of this age. She's an HR 46.

 

[whipper_snapper]

Is it possible to cut large access holes and insert a flexible tank? THese can be made to any size and as long as there is nothing rough or sharp left in the old tanks, they should be supported very well and last a long time.

 

[Sybaris]

Friends of ours had the same problem on a HR, and installed new tanks last summer in Marmaris.

My suggestion is to use a German (I think) system with welded thick PVC sheets. They can be built to any specific size and will last a lot longer than stainless. There is a shop in Marmaris that specializes on this.

Send me an email or pm (or call me) and I will explain in more detail.

Cheers,
Per

 

[nimbusgb]

To be fair, how many people wandering around a boat show with a quarter of a million pounds in their pocket and an itch to buy a boat, look at what's on offer and think ..... I wonder how I'll get the tanks out if one fails in 14 years time?

If more did they'd be buying boats like Amels that do think this sort of thing through ..... only problem is you need 4 pockets full of cash!

Building a boat with the deck off, inserting a lot of furniture and fittings into the hull beforehand saves cost on the build simply by making access easier. What happens 10, 15 or 25 years down the line is probably not the original owners concern anyway.

 

[Nostrodamus]

Totally agree. Boat builders are looking at the cheapest way of building a boat and could not give a dam about what happens once the warranty expires.
We met someone with a Mobo this year who had a minor seal go somewhere in the engine. The seal was pretty cheap but it meant getting the engine out to replace it as it could not be done in situ. The engineer suggested the only way they could get the engine out was to cut a dirty great hole in his deck. So a seal costing a few pounds was going to cost several thousand to put in.

 

[chinita]

Just had the sad news confirmed that my ss steel water tanks are leaking. The boat was built in 1997 so I feel this is premature. We discovered that it (They) were leaking at the end of last season. There are two tanks joined by a single pipe and filler fitted under the cabin sole. We had hoped that the problem was with the joining pipe, which was renewd and replaced but it has now been confirmed that both tanks are leaking. How two lots of corrosion presumably on the welds manifest them selves at the same time after 14 years beats me.

The problems now start. Removing them is bad enough but they wont go up through the companionway so have to be cut up down below and how to get the new ones in. Will have to make them smaller I suppose and have three tanks instead of two, all joined together. You are talking 1000 L here.

The cause I guess is some thing to do with the hard water we have been taking on board in Greece and throughout the Med over the past 8 years.

I am lucky I am still working and able to throw money at the problem to make it go away. I don't suppose I will get much change out of 4,000 in the end.

Any one else faced this problem with a boat of this age. She's an HR 46.

My HR 36 (seven years old at the time) had a fresh water tank leaking. Thankfully it was relatively easy to remove as it was athwartships under the saloon seating on the portside saloon forward bulkhead.

I discovered the leak was due to the weld failing on the underside at one of the corners.

I fixed it with cold weld along the seams, a very simple job, which cured the leak.

Is this worth trying before you carry out destructive surgery!?

 

[Tranona]

Just been through that exercise with an SS tank that had been fitted to my Bavaria to replace one of the plastic tanks. Weld failed after about 5 years. Tank had been foamed into place - took best part of a week getting it out uncluding having to cut away part of the bunk top. Had it repaired with a patch as otherwise it was in good condition, but re-installed it such a way that it will be easy to remove next time!

If you want to replace with plastic tanks (best choice) then Wolfgang Baumann in Gouvia www.top-tank.com does a brilliant job.

 

[Richard10002]

My immediate thought was flexible tanks. Cut a hole/holes in the existing tank tops and protect the edges. Make easily removable covers. attach new tank to filler etc. Pop covers on. Job done. No need to remove old tanks. New tanks slide in in their deflated form.

A friend of mine did a dissertation on flexible tanks in 1983, so I'm guessing the technology is fairly advanced 30 years on.

 

[ksutton]

My immediate thought was flexible tanks. Cut a hole/holes in the existing tank tops and protect the edges. Make easily removable covers. attach new tank to filler etc. Pop covers on. Job done. No need to remove old tanks. New tanks slide in in their deflated form.

A friend of mine did a dissertation on flexible tanks in 1983, so I'm guessing the technology is fairly advanced 30 years on.

Internal tank baffles in the existing tank may prohibit the insertion of a flexible bag.

 

[grumpygit]

Oh the joys of mass produced boats, the balance sheet is first and foremost in the builders mind and bugger the rest!

_______________________________________________________________________

 

[fergie_mac66]

Find the leak clean and epoxy a repair

 

[Tranona]

A friend of mine did a dissertation on flexible tanks in 1983, so I'm guessing the technology is fairly advanced 30 years on.

Rather the opposite - the ones currently on the market are relatively low quality compared with what is possible. Flexible tanks were popular 20-30 years ago made of high grade materials but as a consequence became expensive compared with rotational moulded plastic, which is what is used in most production boats now. For custom made tanks there is not a lot to choose between SS, aluminium and welded plastic, with the last named probably the best.

Just to give an idea, as noted in my last post have just dealt with a failed SS water tank. Cost of welding, adding some tags for mounting and putting in an inspection/cleaning hatch £150, new tank £600 in SS and £680 in plastic. Plastimo triangular flexible of same capacity (130L) £80. But flexible would not fit into existing tank, even with a big enough access hole because of a baffle.

As a guess, based on the volumes they use, I expect the original Bavaria tank would have cost them around £100, based on the price of similar capacity standard size moulded tanks.

 

[Robin]

Oh the joys of mass produced boats, the balance sheet is first and foremost in the builders mind and bugger the rest!

_______________________________________________________________________

If this was on a really mass produced boat like the ones frequently pilloried on the forums there would be all sorts of snippy comments about cost cutting, poor materials and so on. This is on a Halberg Rassy 46, not a builder known for low cost boats yet this is seemingly very poor construction with welds failing after 14 years, and a similar fault reported on a HR 36 at just 7 years old.

We had water tank welds fail at 10 years on a Westerly 33 in 1988 and had to have a new tank made. The fabricators we used for the new tank were very critical of the poor welding on the original tank and used a different technique (don't ask me what now) that they said would be much better. The replacement tank was still OK after 16 years that I know of and may well still be now some 22 years on for all I know.

Our last boat was a 1988 Jeanneau with three stainless steel water tanks, stainless steel holding tank and stainless steel fuel tank. Twenty two years on when we sold that boat they were all leak free and probably still are today. All of those tanks could be removed without major woodwork dismantling and all would have passed out through the main hatch and companionway without surgery. So on that basis I would say that production line building that is well thought out and planned works very well indeed.

 

[duncan99210]

Not had a failure requiring replacing a tank but have had a crack in the top of one water tank in our Bavaria 38 (repaired with epoxy) but this made me look at the probem of replacing the tanks. On our boat, all 3 tanks (1 fuel, 2 water) can be removed without needing to remove any mouldings or woodwork and will (just) fit through doorways and companionway so you could replace them without significant surgery. Compare to a friends HR, where a spilt fuel tank required the removal of the galley and the engine..... Sometimes the designers of the bulk production boats do get it right.

 

[Boo2]

Just been through that exercise with an SS tank that had been fitted to my Bavaria to replace one of the plastic tanks. Weld failed after about 5 years. Tank had been foamed into place...

Foamed with what may I ask ? My surveyor suggested putting something soft between the tank and hull on my boat, I was thinking of using an old closed cell camping mat but if there's an alternative I would prefer that.

...took best part of a week getting it out uncluding having to cut away part of the bunk top. Had it repaired with a patch as otherwise it was in good condition, but re-installed it such a way that it will be easy to remove next time!

With expanding foam wouldn't it be possible just to wrap the tank in thin polythene sheet before dispensing the foam ?

Boo2

 

[sunshinesailing]

Tanks

Hi Mocruising.
Sorry to hear about your tanks. Not all builders are as short sighted. You know our Jeanneau. We have seven ss fuel and water tanks. All removable between floor stringers and bunk supports after releasing hold down straps and removing ss hose clamps.
The tanks design and construction is good. In cross section the tank bottom, sides and 25mm perimeter flange is one piece bent to shape. The tanks ends are a rolled seams. Similar to a steel fuel drum, something close to your heart. The tank top is a flat piece bolted and gasketed to the perimeter flange. The lid holds the fill and vent, fuel pick up and return, access panels and baffles spot welded to the underside of the lid. The water tank interconnecting piping uses bulkhead fittings which require annual tightening. You can actually undo the bolts and remove the lid leaving the bathtub in place.
There is a downside, we have a lot of ss hose clamps to inspect and tighten annually. There is one fuel weep. When the fuel fill pipe is full to the deck there is a weep at one corner of the lid flange until the fuel in the pipe is burned off.
Smooth sailing.
Sunshine sailing.

 

[Latestarter1]

Marine grade alloy is the correct material for tanks, stainless is hopeless.

 

[Tranona]

Foamed with what may I ask ? My surveyor suggested putting something soft between the tank and hull on my boat, I was thinking of using an old closed cell camping mat but if there's an alternative I would prefer that.

With expanding foam wouldn't it be possible just to wrap the tank in thin polythene sheet before dispensing the foam ?

Boo2

Think it was just ordinary builders foam. Reason for foaming was that the tank is shaped to more or less the shape of the triangular space under the bunk, but flat at the bottom. The tank fitted through the hull partly sideways because in plan it was a bit bigger than the hole. Wedged in with balks of timber and foamed in right to the hull sides and under the bunk top. Not the best way of doing it - but it was done in Greece and they always tell you they know wots best! Getting it the worst bit was cutting the foam between the sides of the tank and the hull.

Anyway, it was good enough to repair so I had tags welded at the back and a bar in the front so that I could bolt it to the bulkhead and down to a substantial floor I bonded into the hull. Glassed in a 15mm ply platform for it so sit on, resting on strip of DPC. Two beams over the top, and wedged under the bunk to finish it off. Real belt and braces, but easy to remove when it fails again as it will do, but that's the next owner's problem several years down the line. If I was keeping the boat long term would have bit the bullet and had a new Tek Tanks made.

 

[silver-fox]

Marine grade alloy is the correct material for tanks, stainless is hopeless.

I do believe your advice falls into a category best described as "always certain but sometimes wrong"

What alloy are you referring to ?
In what way is alloy superior to plastic?

 

[grumpygit]

If this was on a really mass produced boat like the ones frequently pilloried on the forums there would be all sorts of snippy comments about cost cutting, poor materials and so on. This is on a Halberg Rassy 46, not a builder known for low cost boats yet this is seemingly very poor construction with welds failing after 14 years, and a similar fault reported on a HR 36 at just 7 years old.
Our last boat was a 1988 Jeanneau with three stainless steel water tanks, stainless steel holding tank and stainless steel fuel tank. Twenty two years on when we sold that boat they were all leak free and probably still are today. All of those tanks could be removed without major woodwork dismantling and all would have passed out through the main hatch and companionway without surgery. So on that basis I would say that production line building that is well thought out and planned works very well indeed.

Whatever makes you think HR is up and above modern yacht construction techniques?
The higher the cost of the end product does not always make a boat foolproof, it's down to how it's built and with what.


1988, may be you've answered your own questions.......

___________________________________________________________________