Water in fuel again!

[sogood]

Just in the last day or two I've been out at the boat tinkering on a few bits and pieces in readiness for the impending splash. I went through the motions of firing her up, just to blow off the cobwebs etc. Anyway, despite a fully charged battery she refused to fire up. She did sputter a little at first and backfired, but that was it.

Prior to this, late last year, she fired up almost immediately and idled fine.

When I'd bought this boat as a bit of a project, she had been sitting for quite a while with a tank half filled with very stale, watery petrol. I drained the tank fully, cleaned out all the fuel lines, replaced some, fitted an inline filter and a new water separator, which I've since replaced again, as it was my plan to replace the separator quite frequently to get everything cleaned up.

Fresh fuel and a rebuilt carb and away she went, until now!

I had ran it lots of times, on muffs, putting it through its paces with no issues.

So I took the water separator off and found it to be filled with a brown watery fluid, that smelled something like petrol! So, a new water filter ( properly primed) was fitted and tomorrow I'm going to clean out the fuel lines and carb and try to run it on a remote tank. I have about 120 litres of fuel in the tank which I'll probably have to drain out and see what it's like. I poured the contents of the old filter into a glass jar to let it sit and I'll see how it settles tomorrow. I'm thinking the water should settle at the bottom, and if so, any water in my tank should likewise be at the bottom, where it is drawn from.

Then I have to see where the water is getting in. Is it possibly condensation? As part of the refurb, I replaced all fuel hoses, including the fill hose, vent and feed. I sealed everything up tight, including the fuel sender, as I had to replace it. I also sealed up the base of the fuel cap where it sits into the deck/gunwale and replaced the rubber O ring in the cap. We have had a very wet winter with some torrential rain at times, but everything is buttoned up tight as far as I can see.

Time for some head scratching!

 

[sarabande]

Any condensation product will be minimal in volume, so if you have a cupful or more, there are a number of choices:

1 a leak - which you have checked for and covered in the rebuild

2 a microbial infection (bacteria or fungi)

3 water absorption in petrol biofuel


If you drain some fuel, it should be clear and no cloudiness. The slightest hint of no sparkle and you may have to drain and polish.

My money if the boat has been left for a while is that you have a mixture of microbes and water absorption. A fuel bug additive and a polishing seems to be the answer, plus a clean of the tank to prevent re-occurrence.

 

[Boatbore]

sorry to hear of your troubles. To me it sounds like you’re doing all that you can, but I would check everything.... including tank breather and the actual cap of the tank. It sounds like a more serious water ingress problem than just condensation.

Look for something unnatural, like if the boat was stored on a slope, even a gentle one, then is water settling somewhere where it can get into the fuel system. You mentioned heavy rain, so you are already halfway to assuming there is actual water ingress somewhere.

When it comes to contaminated fuel, I am also a believer in just starting again rather than trying to clean the old stuff..... unless you have access to a sophisticated centrifugal cleaner, you will never get all the water out of it, and for the relatively small amount you are talking about, despite it being expensive, I would just dispose of it (sensibly of course) .

It might also be worth giving some detail on here of what boat and what engine you have as perhaps someone on here will know of a particular weakness and, more importantly, how to solve it.

 

[sogood]

Thanks for the responses. I forgot to mention the details in my first post. It's a Wellcraft Sportsman 250, with a Mercruiser 5.7 V8.
Today I looked at the fuel from the water separator that I'd left sitting overnight in a glass jar and I didn't see any discernible "separation" or settlement of water and petrol. It was all a rather opaque brownish colour. This reminded me of the colour of the old original fuel that I drained from the tank during the refurb. At the time, I was concerned about any varnish/goo deposit that might have been left inside the tank, but having no real way of cleaning the tank effectively I decided to risk living with it. (Mea culpa!)

The tank is aluminium and holds 100 gallons when full and is buried in foam within it's coffin, between stringers. About 3/4 of the tank runs up under the deck floor and it can't be removed without some serious cutting etc. which I was reluctant to do. I had thought about cutting an inspection/access panel out of the top of the tank, which would facilitate a proper cleaning of the inside. This panel would be replaced with a heavier gauge aluminium panel, sealed and screwed down, just like the fuel gauge sender.

I had tossed this idea about on another forum at the time and was discouraged from doing so, but not convincingly. So I didn't do it, but with a view to possibly doing so in the future if the need arose. I think the future has just arrived!

So I think that's the way I'm going to go. I want to avoid the possibility of going through all this again, or when I'm out on the water!

Any other thoughts most welcome.

 

[Boatbore]

I would recommend running the engine from a clean fuel source too......just so that you know you are on the right track.

The brown fuel doesn’t sound good......but I don’t know what that is. Especially if you think you’ve seen it before. I don’t think there’s is varnish on the inside of the tank though.......

Could the brown stuff be fuel bug ? What does the filter look like ?
Good luck

 

[BruceK]

You say the boat had been standing previously for a number of years? Petrol looks like black tea now? Varnish. The new fuel is dissolving it. Common problem in classic car restos. Take it to a radiator shop to be chemically cleaned if you can get it out. If not Google a home remedy from the classic car forums. Beware though, it's like anchor threads.

 

[sogood]

I'm not sure how bad the fuel is. I'm going to compare it to known fresh fuel. It's not as dark as I suggested and compares well to images I've gotten online while searching the topic. I will try to run the engine from a remote fresh fuel source. Getting the tank out isn't an easy option. Otherwise I would have done so during the refurb. We shall see and thanks for the input.

 

[Bouba]

Thanks for the responses. I forgot to mention the details in my first post. It's a Wellcraft Sportsman 250, with a Mercruiser 5.7 V8.
Today I looked at the fuel from the water separator that I'd left sitting overnight in a glass jar and I didn't see any discernible "separation" or settlement of water and petrol. It was all a rather opaque brownish colour. This reminded me of the colour of the old original fuel that I drained from the tank during the refurb. At the time, I was concerned about any varnish/goo deposit that might have been left inside the tank, but having no real way of cleaning the tank effectively I decided to risk living with it. (Mea culpa!)

The tank is aluminium and holds 100 gallons when full and is buried in foam within it's coffin, between stringers. About 3/4 of the tank runs up under the deck floor and it can't be removed without some serious cutting etc. which I was reluctant to do. I had thought about cutting an inspection/access panel out of the top of the tank, which would facilitate a proper cleaning of the inside. This panel would be replaced with a heavier gauge aluminium panel, sealed and screwed down, just like the fuel gauge sender.

I had tossed this idea about on another forum at the time and was discouraged from doing so, but not convincingly. So I didn't do it, but with a view to possibly doing so in the future if the need arose. I think the future has just arrived!

So I think that's the way I'm going to go. I want to avoid the possibility of going through all this again, or when I'm out on the water!

Any other thoughts most welcome.

Just had a quick look on the Wellcraft owners forum, and it looks like the tank can be removed. Could be a different model or year, best to take a look
http://www.wellcraftboatowners.com/viewtopic.php?t=209

 

[sogood]

So, today I hooked up my primer bulb to the inline filter from the tank and drew some fuel from the tank. It was quite cloudy and a sample of it wouldn't ignite, no matter how I tried. I then left a sample of it in a clear container while I continued drawing fuel from the tank. Within a few minutes you could see the clear separation of petrol and water in the sample. It was about 1/4 of a litre and the proportion of water to petrol was about 1/5th water. I continued taking petrol from the tank and another sample took longer to separate with the proportion being down to about 1/30 part water. Getting places. This sample ignited easily and burned freely. Then rain stopped play, so tomorrow I'm going to continue drawing petrol from the tank but via the sender gauge opening, as I can get right down to the very bottom of the tank this way, as opposed to drawing it through the fuel pick up. The trailer is tipped up at the front so that the tank is raised, with the contents gathering at the pick up at the back end of the tank. I'm hoping to get enough water from the tank and then start the engine on a fresh remote tank. Then after it is warmed up enough, I'm going to try it from the main tank and see how we get on.

I also have to find where the water is getting in. As previously stated, I replaced all fuel lines, hoses, vent etc. The vent fitting on the outside of the hull is sealed at the hull and is pointing down and back, as recommended. I do have a recurring pool of water that forms on the floor of the loo, which is on the same side as the fuel fill, so I'll be investigating that further. I'm thinking that water might be getting in beneath the gunwale, via the base plate fixings on the walkaround rail.

As part of my refurb, I replaced the fuel fill hose, double clamped both ends and resealed the fill flange/base where it fixes down on deck. I also replace the rubber "O" ring inside the cap itself. I'm thinking of making a plastic "washer" that will go beneath the filler so that it's raised off the deck. Anything from 1/4" or more would be an improvement.

I'm also considering modifying or changing the fuel filler as it currently sits flush with the walkaround area on the gunwale. This area forms a channel for all the rain that falls on the front half of the boat, either on the roof or front deck area. I suppose being flush it isn't a trip hazard but I could easily live with a raised cap as opposed to constantly getting water in the tank. For what it's worth, I have/had about 120 litres of petrol in the tank, so the proportion of water shouldn't be too great. It's mostly I think settling low down, by the pick up tube, so fingers crossed.

If I get it sorted, I'll think about removing and cleaning the tank next winter.

Will keep you posted and thanks for the responses.

 

[Boatbore]

Dividing this into 2 issues.

1. Getting the water out of the existing fuel.
2. Stopping water getting into the tank in the future.

1. You could try and use one of those water absorbing sock things. I’ve never used one, but they claim to do exactly what you need.

http://www.commercialfuelsolutions....MIlNLomISv2QIV7ZztCh3bxgWFEAQYASABEgKwh_D_BwE

2. Stopping water getting in in the future. The most obvious culprits are the filler and the breather......check and double check. You could put a trap in the breather hose relatively easily, which you could then check in the future. Raising the filler cap is another effective solution. You mention that you put a new o ring on the existing filler...... that rings a bell with me slightly and I wonder if it’s possible that you have used one that it is perhaps too small.......

Don’t forget that even when the fuel is clean enough to run the engine you still need to clean that tank out as well. That much water in there breeds all sorts of nasties. If you’re able to siphon the existing fuel out then do it and try and get that tank as clean and as dry as yôu can before refilling. In an earlier post I said that I would abandon the 120 litres of dirty fuel...... if you are confident that you can separate the good from the bad, maybe you only need to abandon a smaller portion but I wouldn’t try and be too clever. Dirty or contaminated fuel is a boating problem that can linger on and on, clogging filters, and spoiling days out on the water and it’s not worth trying to save a few quid by hanging onto poor fuel.

 

[sarabande]

Some fuel filler caps have a built-in lever to unscrew it. Any chance that the housing for the lever is corroded through ?

The amount of water you are getting in the tank is indicative of a big entry hole somewhere in the system.

Other candidate: top of the tank with pinholes ?

For peace of mind and safe boating, I think that tank has to come out...

 

[sogood]

Thanks for the input guys. I realise that in an ideal world, the tank would come out, but that would scupper plans to get her in the water this season. My free time will come to an end soon as my work/tour season will kick off shortly. This means I'll be away from home for periods of a week or more at a time, so evenings and weekends to potter won't be available to me. The short stints at home would be when I actually get a chance to get out on the water.
I know it would be for the best to get this sorted once and for all, but for the moment I'll go through with my current procedure and won't consider splashing her unless I'm 100% satisfied that all is well. I'm also going to put another water separator on the fuel line. I'm looking at the ones with the clear glass bowl and outlet to drain accumulated water off. The current factory fitted separator doesn't give you the luxury of actually seeing what's going on and would be changed once or twice per season, in my case at least. It's a very small expense in the overall scheme of things. I'm also looking at the various fuel additives/cleaners etc. and any suggestions in this regard are most welcome.

Taking the tank out is indeed doable. It just means dismantling and undoing a lot of what I've already done in regard to replacing the cabin panels and associated works.

I have some plans for the end of the season when it would come back out of the water, so if it could wait until then, that would be good. Meanwhile, it's raining here today so nothing being done but the forecast is looking good for the coming week. Fingers crossed.

Thanks again for the responses.

 

[Boatbore]

Given your circumstances I wouldn’t take the tank out. Even though that’s is the ideal long term fix. But I would do everything I could in the meantime.

1. Take dirty fuel out. If you can get limited access to the tank via the sender, then use that and try and get everything out...... I would then see if I could come up with an inventive way to try and rinse the inside of the tank with clean fuel...... maybe using a garden sprayer or similar......I would then remove that rinsing from the bottom of the tank too. I would probably use some sort of sponge or sock to get the last bits out.
2. Check filler cap again. Make sure that the o ring is the correct one, and if necessary improve that..... some systems have an o ring on the filler mouth and on the cap (in the lid etc). Exhaust every possibility here until you are confident that the filler is not the source of the leak.
3. Same with breather hose. Check every possibility, and if necessary increase the length of the breather hose so that it dips below the level of the tank...... so that water fills the pipe, not the tank. You could even put a trap in here (just some sort of metal vessel with the in and out breather tubes attached through the lid.
4. Someone mentioned pin holes in your tank. Is that possible ? And if it is, would they allow water in.....i.e, does water get to the outside of your fuel tank ? Do you ever smell fuel in the area where the tank is ? If there’s holes in the tank you would definitely smell it..,.... and as this would be extremely dangerous please don’t let’s gloss over that detail at all. Petrol vapour is what blows up..... Earlier I suggested pressure testing the tank. Any plumber has the kit that can do that. That will determine that one.

Finally. It sounds as if you are going to try and deal with the problem by simply removing the water from the existing fuel and then just carry on, with extra separators to stop it repeating. I’m sorry to say that won’t work, And sooner or later you will Breakdown as a result. As a reminder, Boats only ever breakdown at the worst possible moment......as you are coming in to a berth, or perfecting a delicate manoeuvre....... mostly that will only damage your pride but what if the ferry is bearing down on you at that moment ? Seriously....... bad fuel is the simplest thing to sort out.....so please do try and get this sorted.

 

[sogood]

Hi again guys and thanks for the responses. I'm trying to cover all the bases in sorting out this issue. Locate the source of water getting in, deal with that and set up as much preventative measures to minimise any future occurrences.

The tank seems sound and shows no evidence of leaking/pinholes, with no petrol smells at all. Fuel pickup/feed line is all snug with no signs of corrosion or leaking. Vent hose is looped with exterior vent fitting sited and positioned as it should be. I replaced the defective fuel sender gauge during the refurb and cleaned the mating surfaces of the sender base plate and tank before sealing it, prior to fitting. I was particular about this as I felt that this was where the original water ingress might have occurred prior to me buying the boat. The OP had removed the sender and hadn't resealed it very well and didn't replace all the screws!

The only real contender I think, is the fuel filler, thanks to it's poor design and location. It's like a manhole cover, nice and flat/flush, sitting in a gutter, with raised sides. I'm looking into raising it, relocating it, or replacing it with a different design.

I'll be drawing more fuel off the tank via the sender access plate. Fully cleaning the tank in situ would be a bit of a job as the various baffles inside means you can't get into all the corners etc.

If I was to replace it, I'd consider just cutting it out and replace it with two smaller (and so, easier to get into a tight space) tanks, linked together. But that's for another day.

 

[BruceK]

Have you considered the fuel may have been contaminated at source? It's rare but not unheard of.

 

[sogood]

Have you considered the fuel may have been contaminated at source? It's rare but not unheard of.

I don't think the fuel source is the issue. I got the petrol from the same place as I always got it for my car, until I recently changed that to a diesel. There was never any issue during last summer and through the autumn when running the engine. Just recently when I tried, after it had been sitting through a very wet winter, was when I discovered water in the fuel. I came across a "gizmo" in my box of bits, which I'm making into a raised base for the filler cap and I'm going to make a sort of domed cover for the filler cap also. The actual fuel cap is recessed into the filler body and is a crazy design. I'll post some pics of what I'm at when it's done. I have another water separator ordered and got some fuel cleaner/additive, so hope fully I should be further along tomorrow.

Thanks for the input.

 

[Seastoke]

i don't think the fuel source is the issue. I got the petrol from the same place as i always got it for my car, until i recently changed that to a diesel. There was never any issue during last summer and through the autumn when running the engine. Just recently when i tried, after it had been sitting through a very wet winter, was when i discovered water in the fuel. I came across a "gizmo" in my box of bits, which i'm making into a raised base for the filler cap and i'm going to make a sort of domed cover for the filler cap also. The actual fuel cap is recessed into the filler body and is a crazy design. I'll post some pics of what i'm at when it's done. I have another water separator ordered and got some fuel cleaner/additive, so hope fully i should be further along tomorrow.

Thanks for the input.

you could preasure test your tank

 

[Montemar]

I don't think the fuel source is the issue. I got the petrol from the same place as I always got it for my car, until I recently changed that to a diesel. There was never any issue during last summer and through the autumn when running the engine. Just recently when I tried, after it had been sitting through a very wet winter, was when I discovered water in the fuel. I came across a "gizmo" in my box of bits, which I'm making into a raised base for the filler cap and I'm going to make a sort of domed cover for the filler cap also. The actual fuel cap is recessed into the filler body and is a crazy design. I'll post some pics of what I'm at when it's done. I have another water separator ordered and got some fuel cleaner/additive, so hope fully I should be further along tomorrow.

Thanks for the input.

Petrol moves quickly through a car but not in a boat where it can sink to the bottom of the tank and accumulate.

 

[sogood]

So, I fitted the see through water separator filter and after drawing quite a bit of fuel through it, it isn't showing at signs of water whatsoever. Likewise with the latest samples that I've drawn from the tank.

I also did a pressure test on the tank today and all fittings, including the filler cap are airtight. I'm beginning to think that the water that was present might have been the remnants of that which I missed when I first drained the tank, due to old stale fuel and water courtesy of the PO.

I thought I had it drained, and then topped up with about 120 litres of fresh fuel for running and testing on muffs. Due to it being a 100 gallon/ 454 litre tank, 120 litres only covers the bottom of the tank, so it wouldn't have been long before the level dropped, to allow any remaining water to be sucked up. Am I making sense?

I've checked every possible source of water ingress and can't find anything. I'm going to go back into the tank again, with a thinner tube, to get down into the very bottom corner and hopefully get any last water out that might be remaining.

I have the boat raised on the trailer and it's on slightly uneven ground, so it's leaning slightly to port.

I also pulled the plugs (PITA) and they were very badly gummed up with a black oily/watery goo. These were new plugs during last summer! So, they're all cleaned up again and good to go.

We shall see.

 

[rafiki_]

Good luck with this.