Fuel tank issue

telsyork

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10 Apr 2008
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Burton on trent
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Hi folks

we have an issue with the starboard fuel tank on our fairline corniche.

Every time i do the engine checks there is water present ( half a cup) in the starboard fuel strainer/ seperator, nothing but fuel in the port strainer?

The previous owner told me he had seen this happening for the last year.

I have checked thr deck filler seal all seems ok , o ring present, not damaged!

Any ideas what to check/do to resolve this.

Cheers
terry
 
that's not good, how many hours does it take to get that much water in fuel filter/ separator?
what is the tank access like?
where is the tank vent and do the vent holes face down?

the water in the tank -could be from dirty fuel, could be someone didn't put the fuel filler on properly, could be someone put the fresh water hose pipe in the wrong hole etc. forget about the previous owner too late now. The thing to do is get the water out and make sure it doesn't get back in again. If you leave the boat alone for @ 2 weeks the water will settle out and go to the bottom of the tank. There may be a drain tap at the base of the tank, other wise find a way to get a tube/pipe right down to the lowest point in the tank and pump it out until you get clear diesel. You can get cheap fuel pumps and filter assemblies on ebay to make up a fuel polisher once you have the worst out. (just a separate electric pump with its own fuel filter/separator unit that circulate the fuel from the tank back into the tank again)

once things look pretty clear again treat your tanks with FuelSet to get any residual water into suspension and it will just get burnt off in the engine. Keep an eye on your filter cartridges for any sign of diesel bug
 
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I had this problem on my corniche and it turned out to be the filler on the deck, there is only two ways that Amount of water can get in the tank. One is past the seal on the filler and the other is a bad batch of fuel, best to change the deck filler as an easy and cheap job and drain and flush the tank and salvage what fuel you can.

However now I think of it the fuel filler is pretty close to the water filler on the start side
 
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If you suspect bad batch of fuel it isn't just one tank. Your pickup pipe on the good tank may be "vertically challenged"
The bad tank.... does it lie into any wind / weather while the other is sheltered? I only ask because we have quite stable prevailing wind direction where I am. When the wind really gets blowing my starboard air vents have a nasty habit of getting a small pool of water in it before the drain hole. Nasty because when working on the engine and some plonker comes past creating a wake I get an impromptu "ice bucket challenge" should I be working on the starboard side. My tank breathers are much lower down in this cavity / freeboard, by at least a foot, and have a reverse angled type cap to prevent water ingress but if the cap were defunct or broken it would not surprise me in the least to see water in the tanks. Hell if it can squeeze it's way past a porthole seal .....
 
You rightfully identify the most likely cause of water entry. I smother the filler threads with waterproof grease. I have heard tales of water entering around a deck fitting then dribbling into a loose pipe seal beneath the fitting itself. Also check the tank vent is not somehow collecting water.

The tanks on my Turbo 36 had a low point drain on a short stub tube with a 1/2" BSPT plug, about 2" above the tank base. I replaced this with a fitting with a copper tube brazed on about 300mm long. Wind this in tight then mark the upper position of the nut section. I then removed the fitting and bent to tube downward relative to this marking so it picked up as low as possible. This provided the low point pickup for my fuel polishing rig which is a Baldwin pre filter and Holley red top fuel pump mounted to a bent steel plate housing.

Once the water has separated and been polished out the fuel remains perfectly usable.

Photos can be found here www.turbo36.wordpress.com
 
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