Fuel Spill!

[skipmac]

Originally Posted by Ann T. Cate

SkipMac,

If you already keep a log of your fuel hours, so you can determine approximately how much fuel per tank you will need, then you could fill about 90% full, and only go super slow the last 10%. Use the rag or the fuel saver device, as well. Allow plenty of time, so you aren't rushed when you need to go slowly.

Ann

Thanks Ann,

I do log engine hours and keep track of fuel consumption but of course that's just approximate. My tanks have a float with a round dial gauge mounted in the tank and visible if you move the settee cushions and open an inspection hatch underneath. That is actually a bit more accurate than logging and calculating but still leaves guesswork at the end.

I already use the slow fill at the end and rag system. Just trying to find a way around this.

[skipmac]

Originally Posted by nigel1

So its not just me that suffers from this problem. In my case, its just the vent the spits out the odd drops of diesel.
I figure in my case that its due the relatively large diameter of the filling hose (3") compared to the vent hose (.75") and the little skin fitting for the vent on the boats side reducing that even further.
On top of that, I reckon that when sailing, with the boat heeled, fuel gets sloshed into the vent line, and not all of it drains back.
Solution so far is to fill slowly,and have someone hold an oil absorbent pad under the vent to catch the drops.
There used to be a little gizmo on the market, it was a small container with an opening designed to go over the vent fitting at the boats side, and a couple of suction cups to hold it place, the theory being this would catch the drops, but it is no longer made, so maybe it was not as successful as was hoped.

On a ships bunker tanks, the vent area is much larger than the filling pipe. On my tug, the filling lines into each tank is 6", and each tank is served with two 6" vents, and there is never any problem when bunkering.

Ideally on a boat would be a deck mounted gooseneck vent which you could place a jar under when filling, but the disadvantage is that the gooseneck would be susceptible to damage.

No, you're not the only one. From the replies it sounds pretty common.

In my current boat I don't see any spillage out the vent, only blowback up the fill hole so unless I modify the fill and that changes I have only one drip to worry about.

[nimblemotors]

I believe I have the complete Prius fuel system diagram here if that would help,
here it is, attached. I am considering adapting it to my jetboat, so have been looking into it, as I have a parts prius with all of it.

Enjoy the complexity!

Oops, it is too big to attach, can't remember where it came from, search Prius Bladder and you might find it, or PM me your email I can send it direct.

[skipmac]

Originally Posted by Hud3

I used to regularly spill a small amount of gasoline when fueling my Grady White until I bought a "No Spill" fuel recovery device. It's a small bottle with a hole in the side and suction cups, which you place over the vent so that the dribbles go directly into the bottle. Never had a problem after I bought one. Found it at West Marine.

Grady White. Very nice boat. Had one on a Lake in GA years ago and loved it.

So did you only spill out of the vent or did you get blowback up the fill pipe as well. If I was only getting vent spill it would be much easier to deal with.

[skipmac]

Originally Posted by nimblemotors

I believe I have the complete Prius fuel system diagram here if that would help,
here it is, attached. I am considering adapting it to my jetboat, so have been looking into it, as I have a parts prius with all of it.

Enjoy the complexity!

Oops, it is too big to attach, can't remember where it came from, search Prius Bladder and you might find it, or PM me your email I can send it direct.

Thanks. Will try the google search or go to the garage and disassemble my wife's Prius. I'm sure she won't mind.

[Hud3]

Never got blowback from the fill line on the Grady. I did see it occasionally on the sailboat, but used the tried and true paper towel dike method.

Having a bottle of Dawn dishwashing detergent handy is a good way to disperse any small spills overboard. A couple of drops will do the job.

[the_alpine]

Another problem to consider if youve overfilled to the point youre leaking fuel out your vent: SAILING. Get that baby heeled over to the fuel tank side and youre going to have even more spillage.

[ohdrinkboy]

I have a pontoon boat that will do the same thing. It won't even take adding fuel at full flow from a gas pump. I now fill jerry cans and use a siphon from the jerry can to the tank. Siphon flows slower and allows more time to react. If you can see your fuel tank and it is plastic, you can mark it at different levels so you know how much fuel you need to add.

[ohdrinkboy]

BTW - this is the siphon I use....dead simple


https://www.google.com/shopping/prod...CKQBEPMCMAY4Hg

[pbiJim]

I've seen people hold a bailing scoop under the vent to catch the spue. That trick got popular in Edgartown for a while, back in the late 80's, when the Mass. DEP started to get a bit bothersome there.

The vent whistles do work, but you need to get the hang of listening for the subtle change in pitch when you get close to full. If you are in a strong cross breeze, that may not be easy.

I haven't seen this done yet, but it might be possible to use a capacitive proximity sensor to tell you when the tank is nearly full. Many of those sensors have the ability to see through the wall of a tank & sense the presence of liquid on the other side.

[Capt Phil]

Probably the best piece of advice I ever got from my old skipper during my towboat days in the PNW was... 'Don't top off the tanks'. Phil

[Viking Sailor]

This may only work on my sailboat... I have five or six feet of hose between the deck fill/vent and the tanks. When I fill I allow venting through the deck fill and keep my thumb pressed against the vent opening. I stop filling when I can feel air pressure against my thumb when fuel enters the vent line. Works good for me, YMMV.

[Aloha_float]

Install a vent whistle. When it stops whistling, you are full.

[sailorchic34]

Ah, Its actually simple... The air the tank that is displaced when fuel is added will take the hydraulicly shortest/ easiest path. That is the path of least resistance. Oddly enough that is out of fuel fill as the pressure drop across the fuel fill is practically nil, where the pressure drop in the vent line might be 1/4 to 1/2 inch w.c. So while the fuel fill is open its going to bubble.

Plus diesel pumps at marina fuel docks, generally have a higher / faster fill rate. The typical gasoline fill rate for an gas station might be 5-8 gpm. Where as the marine diesel pump might be sized for oh 25 gpm or so. Generally Diesel pumps have a higher flow rate as most diesel pumps, in the usa anyway, service semi's or large boats. I've designed a few fuel docks and fleet service centers in the past.

[nimblemotors]

I went and looked to see how the gas station shutoff works, and it is nothing fancy just detects when the filler neck fills up with fuel.

So then all you really need to do is raise the vent line above the filler tube,
so the fill tube fills up before the vent line does.
Then the pump will shutoff before the vent spills.
If that is not possible, perhaps put a filter in it so the more dense fuel doesn't pass through, but the air does.