replacement fuel tank conundrum in westerly longbow.

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steve yates

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The yard had a look at my tank while she is in pembroke, and reckoned it would come out fairly simply for cleaning and painting, but of course it didn't. The only way to get it out is to cut it up.

They cleaned it in situ, as best they could, and got a lot of black sludge and rust out of the bottom of it, sadly it was that sludge that was keeping the deisel in. Any fuel put in starts leaking from various rust holes! So she is stuck there till I sort a new fuel tank.

The issue is; in situ is a 110l tank, and a custom built tank, that can fit through the access aperture of 455mm sq, can only hold approx 70l.
(450mm sq, for clearance, and max 385mm high (current tanks height) to allow for the connections between tank and cockpit sole.

The max depth here available is 520mm between the bearing and underside of the cockpit sole.

The other alternative is a standard plastic tank 350mm w x300mm h of 42l capacity, and maybe use two of these with a connecting valve, (I understand the renowns have port and stb tanks? )

It seems a retrograde step to replace the tank with a smaller capacity, but unless I want to start chopping up the cockpit, it seems like my only alternative.

I have been quoted around £650 for a custom tank and around £250 for the 42l tank, plus fittings, plus labour.

My questions are, has anyone here successfully replaced a tank on a longbow, and what with if so?

Has the combined experience here any ideas for getting a larger fuel capacity into that space?

And does anyone know of a source of premade tanks at better prices.

I have already emailed tektanks, as quandry suggested them as an eventual replacement when I got the boat.

Thanks.
 
I know nothing, however to get the ball rolling -

If money is tight, I might be inclined to fit the smaller tank, and carry more spare fuel than is usual. Tough 4 gallon HDPE containers are available foc if you keep your eyes open. You should have plenty of space to make a bespoke stowage and it might be possible to arrange matters so that syphoning into the main tank is possible, even easy. Portable tanks can always be carted to a fuel station if necessary.

If you don't like it you can always fit a second tank later.
 
steve yates said:
The yard had a look at my tank while she is in pembroke, and reckoned it would come out fairly simply for cleaning and painting, but of course it didn't. The only way to get it out is to cut it up.

They cleaned it in situ, as best they could, and got a lot of black sludge and rust out of the bottom of it, sadly it was that sludge that was keeping the deisel in. Any fuel put in starts leaking from various rust holes! So she is stuck there till I sort a new fuel tank.

The issue is; in situ is a 110l tank, and a custom built tank, that can fit through the access aperture of 455mm sq, can only hold approx 70l.
(450mm sq, for clearance, and max 385mm high (current tanks height) to allow for the connections between tank and cockpit sole.

The max depth here available is 520mm between the bearing and underside of the cockpit sole.

The other alternative is a standard plastic tank 350mm w x300mm h of 42l capacity, and maybe use two of these with a connecting valve, (I understand the renowns have port and stb tanks? )

It seems a retrograde step to replace the tank with a smaller capacity, but unless I want to start chopping up the cockpit, it seems like my only alternative.

I have been quoted around £650 for a custom tank and around £250 for the 42l tank, plus fittings, plus labour.

My questions are, has anyone here successfully replaced a tank on a longbow, and what with if so?

Has the combined experience here any ideas for getting a larger fuel capacity into that space?

And does anyone know of a source of premade tanks at better prices.

I have already emailed tektanks, as quandry suggested them as an eventual replacement when I got the boat.

Thanks.
Click to expand...

We replaced the tank in Berwick, which is of course the same as a Long bow but with bilge keels.

We removed the two screws from the feet and the filler.

we pulled it forward a little, rotated it through 90 ° around the vertical axis, then rolled it onto what was its back. Then it slid forward and lifted out through the hatch ... just.

We had the new one made a few mm smaller on al dimensions so that it was easy to fit in

However the boat had tiller steering. If you have wheel steering gear in the way the above probably won't work.
 
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I do vic, but it's cables running through both cockpit lockers, though the binnacle is immediately in front of the hatch and could impede a tank?

When you say hatch, I presume you mean the square access hatch on the cockpit floor, yes?

Can you remember the volume of your tank vic? and was the replacement similar with the just shaving off a few mm in dimensions?
 
I'd go for the 42l plastic tank solution purely on a budget basis unless you always plan on doing marathon trips.... I probably only used a single tank the whole summer though so depends how often you would need to be filling up and if you are going to be on a swinging mooring. Horses for courses. I like the arguments for plastic (lack of corrosion).
 
steve yates said:
I do vic, but it's cables running through both cockpit lockers, though the binnacle is immediately in front of the hatch and could impede a tank?

When you say hatch, I presume you mean the square access hatch on the cockpit floor, yes?

Can you remember the volume of your tank vic? and was the replacement similar with the just shaving off a few mm in dimensions?
Click to expand...

Yes the cockpit floor hatch ...... nothing in front of it will cause any problem provided the hatch is the same size.

The tank that came out was the original as fitted by Westerly ... sorry I don't remember its capacity.

The new one was made locally to the same pattern, just a few mm smaller each way to give a bit more wiggle room

For a short time we had a smaller plastic tank sitting in front of the leaking original but we did not make any long trips with this arrangement.
 
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My recollection of your tank was close to a cube shape almost square in plan and almost as tall as it was wide, a big tank taking up a relatively small space. Problem seems to be that boat tanks are usually quite shallow to fit below lockers etc , the 42 litre std. Tek Tank is only 30cm. deep, you must have room for almost twice that? If you could buy a blank and install it upright then put the inspection/connection panel on top on what was the end, or even put two like that you might be able to take better advantage of the space you have? Seems a shame not to use it as that void would not be much use for anything else. However your Yanmar should be good for at least 2l/hr giving you a range of more than 100 miles under motor and you are a sailer. A 20l. container would extend to 150miles and allow you to top up from filling stations when you are in remoter places. You mention clearance for connections, all of that will be on top, nothing under, so you should not need much, but the tank will need to be securely restrained. IIO litre is probably 30% bigger than average for a 30 footer.
Having said all that, I would go for a custom tank as close as possible to the original, you have got off lightly so far with a new engine, new sails and all that junk Lenny left you with and the big tank would mean that you do not have to keep thinking about where to top up.
 
Restraint is something I was wondering about, presumably plastic tanks are not simply bolted or screwed into whatever the steel tank was attached to?

Are they strapped down?

The problem with a tank as close to original as possible is anything that fills the void, wont get through the hatch. It almost seems like the boat was built around the tank!

I would take as much fuel capacity as I can get, as I don't want my port or anchorage choice to be dictated by a need to refill. I also need to bear in mind that when I have to get back for work, I HAVE to get back; It's not like missing a day in an office, it's some poor sods wedding, and missing it will cause havoc :) So If I have to motor hard into head seas and windover tide at end of a trip, so be it. As an aside, when I have been hammering her like that, it's more like 3l p/hr, but I would expect 1.5-2 l/phr if just cruising along without wind or a bit of gentle motorsailing.

I'm leaning towards 2 plastic tanks connected up, but also wondering about the feasability of cutting out a chunk of the cockpit sole and doubling the length of that existing hatch, putting in some sort of crossways batten for strength when walking on it. That may make it easy to install one large tank, and make it easy to access the top of the tank and any fittings?

Anyone ever done anything like that? Or is it a stupid idea? Or an expensive one?
 
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Quandary said:
My recollection of your tank was close to a cube shape almost square in plan and almost as tall as it was wide, a big tank taking up a relatively small space. Problem seems to be that boat tanks are usually quite shallow to fit below lockers etc , the 42 litre std. Tek Tank is only 30cm. deep, you must have room for almost twice that? If you could buy a blank and install it upright then put the inspection/connection panel on top on what was the end, or even put two like that you might be able to take better advantage of the space you have? Seems a shame not to use it as that void would not be much use for anything else. However your Yanmar should be good for at least 2l/hr giving you a range of more than 100 miles under motor and you are a sailer. A 20l. container would extend to 150miles and allow you to top up from filling stations when you are in remoter places. You mention clearance for connections, all of that will be on top, nothing under, so you should not need much, but the tank will need to be securely restrained. IIO litre is probably 30% bigger than average for a 30 footer.
Having said all that, I would go for a custom tank as close as possible to the original, you have got off lightly so far with a new engine, new sails and all that junk Lenny left you with and the big tank would mean that you do not have to keep thinking about where to top up.
Click to expand...

Similar height and width but depth, back to front, smaller.
 
steve yates said:
The issue is; in situ is a 110l tank, and a custom built tank, that can fit through the access aperture of 455mm sq, can only hold approx 70l.
(450mm sq, for clearance, and max 385mm high (current tanks height) to allow for the connections between tank and cockpit sole.

The max depth here available is 520mm between the bearing and underside of the cockpit sole.
Click to expand...

Why not consider a different filler arrangement? If you fit a small round access hatch instead of the existing filler on the cockpit floor, you could have a filler cap on the top of the actual tank. Then have a tank made 450mm square and say 500mm high, giving you 100 litres capacity.
 
I agree with Vic but as the owner of a Longbow - same hull as yours I think - taking the tank out via the hatch in the cockpit may be restricted by the size and shape of your engine. I had a Volvo MD3B, the three cylinder one, and there was no way the fuel tank would wiggle past it!
Anyway, my suggestion would be a smaller, standard size plastic tank and another spare tank. We changed this year from a spare 20l metal jerry can to two 10l plastic cans and they are so much easier to carry to a petrol station or manoeuvre into the locker.
 
I had a similar problem on my Moody33 - the tank was leaking so had to be replaced. Impossible to get out through the hatch so cut up into 3 pieces in situ and removed. I re[laced with a Plastimo tank, also try Vetus and Osculati who all supply 'standard , tanks. Another company is caktanks.co.uk who specialise in caravan, motorhome, horseboxes, campervans etc(and seem to be cheaper than 'marine' tanks!
 
So, I suggested my idea of cutting up the floor/extending the hatch, and the yard had a look and came back with what looks like a much better suggestion.
"Rather than extending the current access hole we would be able to alter your cockpit floor making it removable for when you require full access to the tank, and when put back down it would not look much different to how it looks now. This would also negate the need to construct a new fibreglass access hatch lid, as well as significant additional bracing which would be required.

The plan would be to cut the cockpit floor above the existing bearers (of a decent size), detaching it from the existing bearers in the process.
This would then give huge access to the void beneath, where a large diesel tank can be fitted.
After fitting we would place the cockpit floor back down into its original position (We would need a small amount of bracing to one edge, and would need to apply some waterproof coating to the bearers), however rather than glassing it back down it would be sat on a bed of sealant and screwed down around the edges with stainless steel countersunk screws. Therefor if you need to raise the floor in the future all that would be required would be to remove the screws and slit the sealant.

Your wooden false floor would also sit back into place without modification.

What are your thoughts on this? It would not change the originality of the boat, allow a good size tank installation and be completely watertight.

Once query which has come up is the location of the tank filler. It may be prudent to move the tank filler to a deck mounted filler. It would make fitting the tank much easier, and reduce the chance of filling the cockpit with diesel should a spillage occur when refuelling.

Estimate:

To remove the existing cockpit floor, tidy up edges and form replacement bearer.
Install new fuel tank
Replace cockpit floor, sealing down onto a bed of sealant, ensuring waterproofing and strength

£832.53 + VAT *

* Please note this does not include the cost of the new tank or tank fixings required, but does cover installation.
"
I could then put a 170l tank like this https://www.asap-supplies.com/vetus-rigid-all-purpose-tank-170-litre?nosto=nosto-page-product3. It's more expensive, but it seems to me to be a solution good for another 20 plus years, and give me a robust fuel supply on par with the new engine the boat already has.
A 42l tank would be a lot cheaper, but it would feel like a stop gap, and I would still want the job done properly. If I don't have it done, it's a £1500 bill to truck her back anyway. With a new tank and that much capacity, I can just sail her back, especially if I get a weather window like this one :)

What do you folk think of the plan, any big downsides that I am unaware of? Is it overkill? Anyone ever done anything similar?

Thanks, steve



What do you guys think of that idea,
 
steve yates said:
I could then put a 170l tank like this https://www.asap-supplies.com/vetus-rigid-all-purpose-tank-170-litre?nosto=nosto-page-product3. It's more expensive, but it seems to me to be a solution good for another 20 plus years, and give me a robust fuel supply on par with the new engine the boat already has.
Click to expand...

I suspect that I have missed an earlier part of a saga, but why would you need 170l of diesel? Is it for running heating while you're living aboard? If you don't get through it reasonably quickly, and at least once a year, that's going to be an awful inviting diesel bug farm.

That said, it sounds like a good scheme, at a pretty reasonable price. Could you fit two or three smaller tanks in the space and keep all but one dry when you're not doing long distance stuff?
 
I wouldn't NEED 170l cruising uk coastal waters, but it could be useful to have for going further afield to the Faroese or Iceland, or across the Atlantic.
She will prob be in the med for a while in a few years, and it sounds like a lot of motoring could be on the cards there.

For delivering her round lands end in winter to Essex, I want the ability to punch against wind and tide all day if required, which burns approx 3l/hr, and I don't want to have to keep seeking the shore and fuel supplies
I used approx 120l / 300miles/ 50 hrs between maryport and milfordhaven,

But the main reason is there is very little relative difference in the price of the fuel tanks, £60 difference might be another 100l, so better to have it than be compromised without it.
I don't have to fill it to the brim all the time, and I don't really believe in the condensation of water theory inside the tank.
If I was happy with 42l, it would be job done,
 
Well, it will certainly keep the rudder in the water. It seems an awful lot of fuel to carry probably about twice what most people would need and if it is half full the tank baffles will need to be effective to keep it from slapping about, 100 litres of fuel is a fair weight.
But my main concern would be the joint between the floor upstand and the cockpit sides, if it is really water tight (and surely it needs to be?) it will be very difficult to remove. Since the tank should not need to come out again for about 20 years or so. why not just glass the floor back in. If you imagine a box , it depends for its strength and stiffness on the bracing provided by the shape so the bottom is much stiffer than the top. To compensate for this loss of strength you may need to use stringers round the edge of the new opening with strong joints at the corners, I think I would be happier to restore the shape and cut it out again in 2040 if necessary.

Edit,
Looked again at your proposed tank , the moulding divides it effectively in to two so it is well baffled.
 
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steve yates said:
I don't have to fill it to the brim all the time, and I don't really believe in the condensation of water theory inside the tank.
Click to expand...

Neither do I. It's more the matter of fuel containing biodiesel sitting in the tank for long periods which would worry me. In your case I think I would fit a 40l tank for general use and a 130l one to fill only for long range trips.
 
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