Water in deisel tank and black primary filter.

Quandary said:
Regarding all these attempts to scare, any boat with a ten year old fuel tank will have some 'crud' in the bottom, I know I have cleaned out tanks in the past so for years I must have been going about with dirt in them, but then that is what filters are for. This tank has had all the reachable 'crud' removed and is probably cleaner now than it has been for ten years or more. The difference is that by sampling the fuel on the bottom we know there are black rust specks there, the fact that Westerly got away with installing a steel tank in an inaccessible position with no access to inspect or clean it is far from perfect but they must have thought it was okay. If the secondary filter had been dirty I would have more concern for the engine the fact that it was clean gives me a lot of confidence in the system.
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If you are happy to think that then best of luck.:encouragement:
 
Quandary said:
Regarding all these attempts to scare, any boat with a ten year old fuel tank will have some 'crud' in the bottom, I know I have cleaned out tanks in the past so for years I must have been going about with dirt in them, but then that is what filters are for. This tank has had all the reachable 'crud' removed and is probably cleaner now than it has been for ten years or more. The difference is that by sampling the fuel on the bottom we know there are black rust specks there, the fact that Westerly got away with installing a steel tank in an inaccessible position with no access to inspect or clean it is far from perfect but they must have thought it was okay. If the secondary filter had been dirty I would have more concern for the engine the fact that it was clean gives me a lot of confidence in the system.
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+1 The engine polishes the fuel whilst operating as it pumps more fuel than it needs through the filter and returns it to the tank,as long as you check the primary filter frequently to start with it will probably be ok with the work you have already done.
certainly not worth removing tank for replacement.
 
A1Sailor said:
What would an insurance company expect a prudent owner to do?
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What the surveyor said needed doing. If not mentioned by surveyor. Normal routine maintenance. Annual service. I suspect the actions so far would be acceptable. Problem detected, Reasonable action taken, Follow up with reasonable monitoring.
 
lpdsn said:
Incidentally, I wouldn't get hung up on the date on the filter - they don't expire so you don't know when it was fitted. I bought a dozen at once and (hopefully) I won't use the last for some time now, by which time it might appear old
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No, I meant the date it was replaced was written on the end in marker pen, 26/10/2006, not the filters manufacture date.
So it's been in there for 10 years.

Would anyone expect their primary fuel filter to be relatively clean after 10 years?

The tank simply cannot be removed before launch day, there is no time, and lift in is is only one day a year.
A new tank would be a wise long term investment, but it's a longer term job to be done, along with replacing the steering cable, and the forecabin headlinning at some point in the future.

A vacuum gauge looks a good idea, and a water separator definitely, if I have time to fit the, before launch, if not I should have time to do that before I take her to maryport.

Surely the primary fuel filter would do its job and keep crud out of the system until it becomes clogged? And that could be used as a gauge ?

The previous owner was very much a careful man, he left the tank full, and dosed with biocides before lay up, he just didn't anticipate a 3 year layup, which has allowed water into the tank.

I will check the filters again in return, and then run the engine on launch, as Quandary suggests, and check the filters again.

Here is my main question, is there any potential downside to pumping out all the fuel? I.e. Disturbing any crud at the bottom?
 
Having some crap in the tank would be normal. Know you had 40 liter of water sitting in the tank for up to 3 years. Hmmm.
Ok water gone.
Some bug and loose rust left. How much? unknown.

Quandary is right. This is why you fit a water trap and filters.
What to do if the engine stops? It's a sailboat put the sail up. No wind drop the anchor.

Just a stupid suggestion.
Fit an other extra filter. Possibly even parallel to the existing filter. So if one starts to get bunged up you just switch over a Y valve and keep on running while you clean or change the bunged up filter.
If you find bunged up filter are a recurring problem. Clean or replace the tank. If not then problem with the fuel is solved.

Personally just for piece of mind. I would be tempted to at least pump out all the fuel in tank let it settle and filter it.
I might even be tempted to use some of the old fuel after it had settled to flush out the tank some more.
Disposing or using would depend on what it was like. After I had let it settle.

I would also want to inspect the tank. Even if there is no inspection plate. Perhaps you can see enough with a mirror or camera after disconnecting filler pipe.

My worry wouldn't be so much about bug or floating little bits of rust.
I would be concerned about pitting in the bottom of the tank if it was just a steel tank which had water sitting in it for up to 3 years.
Might not put it on my immediate agenda. But a new tank would be on my wish list. A leaking fuel tank would just be a problem I don't want to have deal with.
 
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steve yates said:
A vacuum

Here is my main question, is there any potential downside to pumping out all the fuel? I.e. Disturbing any crud at the bottom?
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I took two samples yesterday, into the white bucket, the first, from the very bottom of the tank, about three litres, had fine black specs in it when it settled, the second from just above the tank floor was clean red diesel, there was no water in either (and no sign of bug so the biocide seems to have worked) I put the clean diesel back and just dumped about a litre with the bits in it. I put a magnet down through the filler hole and dragged it about several times, it did not bring out much each time but in a steel tank that is not surprising. There are definitely still black specks lying on the floor of the tank, every time I take a sample from there it will get some more out and with a dry day and nothing better to do I may try a bit more.

I am comforted by the more common sense later replies from experienced folk who seem to have grasped the problem, and agree that the eventual solution should be tank replacement. Putting another water separator type filter in the locker in front of the tank should be a relatively straightforward job but if the tank is to be changed, the two existing filters in line should be enough. The idea of two new switchable filters in parrallel is more complex but a very safe solution and if you decided not to change the tank, worth considering, But, with careful monitoring, I expect the existing filters to cope with what is there now.
I can see no benefit in extracting the remaining fuel unless we can find some way of cleaning out what is under it. We know that just above the bottom it is clean and the engine runs fine on it. If we get the boat in the water and agitate the tank I can sample again and see what the fuel at the bottom and just above it looks like.
The previous owner prepared the boat for launch a year ago, I am fairly sure I recall the engine being tested? I suspect the water got in when the dead leaves in the cockpit partly choked the drain and allowed it to rise above the filler neck from time to time in heavy rain.
 
It looks like you guys have a reasonable plan. Probably much more thoroughly prepared than most boat move plans.

Bon Voyage. I think you will enjoy the trip. :)
 
steve yates said:
A vacuum gauge looks a good idea, and a water separator definitely, if I have time to fit the, before launch, if not I should have time to do that before I take her to maryport.

Surely the primary fuel filter would do its job and keep crud out of the system until it becomes clogged? And that could be used as a gauge ?
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The advantage is warning. e.g. when mine gets to 8"Hg I think about replacing the filter. 10" is enough to make the engine stutter at high revs. 12" of vacuum stops it.

I'm not sure whether your PO was diligent or not. Marking the date of the filter change says yes, but then leaving it for ten years says no. Anyway, the price of CAV filters online is so low that you can just get yourself a batch and keep a number on the boat at all times.

PS if he hasn't changed the filter since 2006, the engine oil might be ready for retirement too.
 
Strangely the oil was changed when he planned to launch last year and is not even black yet, I suspect he may have changed only the engine filter element.
 
I think the key thing is to be able to draw off water/fuel/crud from the lowest point of the tank.
On some tanks, the only way to do this is a semi-flexible hose with a weighted end, shoved down the filler hose.
Heel the boat to make one side of the tank lower.

In the long run, I think upwards of 100 litre tankage might usefully be split into a bulk tank and a 'day' tank?
 
pvb said:
How would you suggest this is plumbed?
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On my mate's boat, the normal engine feed and return go from/to the day tank.
The normal CAV filters are between day tank and engine.
The fuel is pumped to the day tank via another filter, from port or Stbd bulk tank.
The logical thing might be to add a polishing circuit?
 
lw395 said:
On my mate's boat, the normal engine feed and return go from/to the day tank.
The normal CAV filters are between day tank and engine.
The fuel is pumped to the day tank via another filter, from port or Stbd bulk tank.
The logical thing might be to add a polishing circuit?
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So is the fuel pumped automatically into the day tank? Or does it need manual intervention? Seems like something else to potentially go wrong. There's no discernable benefit in having a day tank if the main tank is properly managed.
 
pvb said:
So is the fuel pumped automatically into the day tank? Or does it need manual intervention? Seems like something else to potentially go wrong. There's no discernable benefit in having a day tank if the main tank is properly managed.
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There is if you sail beyond reliable sources of clean diesel.
Being able to fill the day tank from cans might have a lot to recommend it one day!

"if the main tank is properly managed". There is a constant stream of threads on here where this has clearly broken down.
 
pvb said:
So is the fuel pumped automatically into the day tank? Or does it need manual intervention? Seems like something else to potentially go wrong. There's no discernable benefit in having a day tank if the main tank is properly managed.
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+1 I think Steve should focus on getting a clean tank, it is only 2' x 2'x 18" but perhaps this is big by today's standards, I would expect the engine to burn about 2l. per hour at cruising speed.

The suggestion of pulling the boat over to get the crud to one side and more concentrated is a good one which we might try when the boat is afloat alongside a pontoon, thanks for that idea..
 
Westerly in their wisdom placed this tank, then bolted the deck moulding down on top of it, if there are access panels they are tight up against the grp cockpit floor, with access only though the filler pipe which rises through the cockpit floor, thus our options are quite limited. I am very envious of your access panels. It may be possible to take out a bulkhead, unbolt the tank and possibly drop it enough to allow it to slide back or forward and thus find out if there perhaps is an access panel in the top but that is quite a big job and if going that far I think it would be worth continuing and changing the tank for a plastic one with an access panel.
I had a Sigma 38 with a steel tank under one aft cabin, which started giving problems, I pumped it out and unbolted it with the intention of having it steam cleaned but when I got it in to the main cabin it would not pass through any hatch so I had to resort to a succession of cleaners, solvents and coatings, it was a slow smelly dirty job and I had to shower and change at the Club each day because of my wife's aversion to the smell of fuel.
 
Is there the faintest hint of 'potential' access from either end of the tank? if so - it may be possible to flycut a large access hole and then engineer a flange and closing plate.
 
Fundamentally, it is worth keeping in mind it is a diesel tank, not a maturing vessel for single malt.
The cleaning/polishing needs to be good enough that it reduces loose crud to well within what the filters can cope with.
The filters need to be plenty good enough and big enough to cope with what the cleaning leaves behind.

That is all you need for happy motorsailing!
 
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