Fuel or engine oil leak

[Kommy000]

Hi,
So after changing oil and fixing the belt situation and engine noise thanks to all the replies on these forums, I have another question.
I have a lot of red colored water in my bilge.
I evacuated it before but it keeps on filling up. I'm not worrying about the water portion since there is always some water in the bilge but I'm worried about what in that water.
I was hoping that it was maybe oils spill from previous owner and I shop vaced all the water and cleaned up the bilge the best way I could but for some reason I still keep on seeing lots of red tint in the new water in the bilge. I have special pads in the bilge and under the engine and they are bright red.
I know the engine probably drips a little little bit of oil due to its age but now I'm thinking it might be diesel. After not using boat for a month, the smell inside is pretty strong with engine/fuel smell. Also, last time I filled up, seemed like I ran out of fuel pretty quick. I assumed it might be a bad gauge but I just filled the whole tank 2 days ago and its showing full so gauge is working.
I tried to look at the fuel tank through the small openings and I don't really see any leaks though the area behind the engine looks moist but nothing clearly leaking as far as fuel goes.
Does anyone have experience with this type of problem? I hate to leave big oily spots around my boat when the bilge pump turns on, plus I'd rather not to have strong smell inside the cabin plus on loosing money on fuel. I was even thinking of taking out the fuel tank, but I have no idea how that even possible. I'm guessing I would have to remove the engine and then the plywood divider behind the engine to put the tank forward? Or is there a simpler way.
Any usual spots on the tank that can leak? I checked via small openings and with flashlights the hoses and they all look good. The only portion I can not see is under the fuel tank or the forward section of the tank since it faces the engine and the plywood wall dividing it.
Any suggestions? Is pink water because of fuel or oil?
Thanks

 

[Jim Legere]

Without knowing the specifics of your boat, I'll throw out some guesses. Pink or red fluid in the bilge could be: glycol antifreeze (but not if your engine is raw water cooled), transmission fluid (Dexron), or 'dyed' diesel. I don't know if the diesel that you buy for boats in Florida is dyed red - it is in some states - but that would be my first guess. Leaking aluminum fuel tanks are not uncommon in our old Cherubini Hunters. Good luck

 

[uncledom]

If your "special pads" are soaking it up then it's diesel as they don't soak up water or glycol for as far as I can remember. But it really shouldn't feel like water. Either one should be slippery with diesel being the more oily feeling of the two.

 

[SG]

Unless you have an issue with smell, it's not diesel fuel.
If it was oil, you'd see a shene on the water -- further, it would become an issue with the engine after a few quarts.
You should check the transmission fluid -- but I doubt that is the issue for a variety of issues.
The suggestion that it's engine coolant (also referred loosely to as "anti freeze') is probably a good guess. The only other likely issue would be if you potable antifreeze -- but that's not too likely if your boat wasn't winterized in St. Pete. I assume you have checked the coolant levels to see that the engine itself has coolant?

You might have overfilled the expansion tank with coolant; You might have a leak in the hose to or from the hot water heat exchanger (if you have one); or, you might have an issue with the engine. Do you have some paper towels that you could put under the engine and see what's going on?

 

[tgentsch]

I had a similar problem on my 79 Hunter 27. Albeit not severe enough to make it to the main bilge, only the smaller bilge under the engine. I wiped it up with a rag every time I went out. Two times a year the Yanmar dealer makes a trip to our lake, so I put my name on the list this year and had a general service performed. The mechanic started at the fuel tank and checked everything all the way to the injectors. My leak turned out to be multiple items; a section of fuel line was replaced, all clamps as well, was also missing a few copper seals on some of the fuel fittings, and the fuel pump screws were a bit loose allowing seepage around the diaphragm. Doesn't leak a drop any longer. While he was out he also replaced the water pump impeller and water hoses, there is a noticeable improvement in water flow. The hoses were ancient and could sink the boat. I have a dry bilge these days after adjusting my prop shaft seal, that was where my water was coming in. Just a few drips now when the shaft is turning, textbook.

 

[SG]

I can't imagine diesel collecting in the main bilge without a lot of diesel smell in the boat?

 

[JimInPB]

I think that I would probably dry the bilge with a towel, then dust the area with talc or some similar powder, then sit there with a flashlight & look to see where the wet spots appear first.

 

[Kommy000]

Unless you have an issue with smell, it's not diesel fuel.
If it was oil, you'd see a shene on the water -- further, it would become an issue with the engine after a few quarts.
You should check the transmission fluid -- but I doubt that is the issue for a variety of issues.
The suggestion that it's engine coolant (also referred loosely to as "anti freeze') is probably a good guess. The only other likely issue would be if you potable antifreeze -- but that's not too likely if your boat wasn't winterized in St. Pete. I assume you have checked the coolant levels to see that the engine itself has coolant?

You might have overfilled the expansion tank with coolant; You might have a leak in the hose to or from the hot water heat exchanger (if you have one); or, you might have an issue with the engine. Do you have some paper towels that you could put under the engine and see what's going on?

Sorry I should've been specific. Its 27 hunter so engine is 1GM yanmar which is water cool so it just takes the sea water in. Also the transmission I believe uses regular engine oil.
There is a strong smell kinda like fuel smell and I do see a multi colored sheen on the water once in a while. As far as pads, they are red in color under the engine that is why I thought it was oil since its under the engine but the water in the bilge touches the pads so it brings the fuel/oil in it on those pads. Plus the area under the engine is on the angle from the back towards the bilge so if anything leaking there it will reach the pads under the engine. The area right behind the engine looks sweaty, not sure how to explain. There is no clear run of oil or fuel but the whole wall somewhat oily sweaty appearance.
At this point I'm leaning towards the fuel, especially with smell. So I need to figure out how to remove and replace the original tank and at this point I might as well replace all the hoses and the fuel separator too since it looks pretty old too. Any ideas how to replace the fuel tank on 27 Hunter? Do I have to remove the engine to do that?

 

[SailormanDan]

I just went through replacing the fuel tank this past summer and it was a good news/bad news thing, the bad news was my Yanmar 1GM needed a new ring on the piston, the good news was they had to pull the engine to work on it. With the engine out of the way I was able to pull the bulkhead and replace everything (except electrical wires) related to the engine: tanks, hoses, muffler. I bit the bullet and spent the money figuring that I wouldn't have to do it again for another 35 years.
I don't think you have to pull the engine, do a search through the forum, I think some other folks were able to cut/crush the old tank to get it out and then put a plastic tank in that they could fold up to squeeze back in. (I was able to put a metal one in because I had the room to work) The side panels back along the fuel tank will actually come out to allow you access.
Diesel fuel actually feels oily, so it can be mistaken for motor oil. The diesel here in VA is colored red, motor oil is either honey-colored when new or black when used.

 

[sailor832]

Before I would go ahead replacing the tank I would check all the lines and fittings I think tthey would be a more probable place for a leak

 

[rardiH36]

My 1980 Cherubini Hunter also is exhibiting much of the same. Except only shows up in the bilge. My bilge is normally dry of water. So the oily liquid -- only a few thimbles full every few weeks -- is noticeable.

Took me quite some time to finally rule out other possibilities besides a leaking fuel tank. Because the leak is so slow, by the time the fuel reaches the bilge I think the volatile component has largely vaporized away. So what's left is a thicker oily substance that no longer resembles the stuff we put in our tanks.

Soon I've got to replace my tank. No way will it come out in one piece without cutting up my FRP. On "Ask All Sailors", several weeks ago I posted a query. Started an interesting discussion. Here is the link: https://forums.sailboatowners.com/index.php?threads/an-acceptable-repair-or-wimping-out.187821/

In particular note the warning about possible explosion of diesel vapors in the tank.

 

[centerline]

if there is a fairly strong smell in the boat like diesel or a solvent, then there is definitely a fuel leak. sometimes water will change the smell of the diesel to a solvent type smell. and it may have been in there for quite some time and with the boat heeling when sailing, it could carry the film of fuel over the entire bilge surface area.... so even after stopping the leak, it could be some time before you get the smell and the color to go away. but a good strong degreaser in the bilge would be the quickest short cut to a clean bilge.... a high concentration of bleach water, or my preference is a cup or two of concentrated liquid whitewall tire cleaner poured in with the bilge water... it will dissolve the oil residue in a day of sailing... then drop a couple of oil blankets on top of the bilge soup before removing it, as the blankets will pick up all the emusified oil that may be left floating on the surface. if you dont do this, when the water level lowers, the floaters will still be left setting on the floor of the bilge
but there are other sources that could cause a red tint in the water... a NEW red mechanics rag dropped in the bilge will dye the water for awhile.... or a lost red leaded pencil, which may last for a long time staining the water as it rolls around in there..
as for the more likely fuel leak, dont assume its the tank until you have proof. changing out the tank is much worse than changing any other part of the fuel system... it could be as simple as a loose clamp or fitting, or more troublesome would be a cracked hard line at a fitting due to the vibrations of the engine.
if its possible to tuck oil pads in around the upper parts of the bilge sump, you could cut strips and lay in there so that you can find where the fuel could be dripping in from, and trace the trail back to the source...
if you have water sloshing about under the engine, pump out as much as you can, then use towels to swab out the rest of it... then lay pads in there and run the engine at about 1200rpm for 10-15 minutes and watch for drips on the white pads.. if you see none, leave the pads there overnight and check them later....... im not sure if that engine uses a lift pump on it to supply fuel to the injector pump/injectors, but if it gets a small hole in its diaphragm, fuel will drip out the weep hole as a telltale, rather than running into the crankcase, unknown, and diluting your oil...