My tank was empty

[Brian D]

So I go down to the boat to dress the ship and start my motor. I let it run whenever I am on the boat just to keep it in shape. So I check my fuel gauge which was around 1/4 full last month. It is on E now.

Not sure if I have a slow leak (I don't think so) or it is evaporating (which I doubt). I have never seen it on E before, never since I have owned the boat. So my only conclusion is someone siphoned my tank dry.

Wonder if I can get a locking fuel tank cap. Man that irks me to no end. :cussing:

 

[Delezynski]

Is the gauge good? They go bad. Stick the tank to make sure.

Greg

 

[Ross]

Can't imagine anyone successfully siphoning from a boat fuel tank. mine is below the WL.

 

[Brian D]

Mine can be siphoned. I have done it myself. I have a swim step that is just below the fuel tank level. As for the gauge, I will check it out. It is a new gauge and was working fine when I put it in. It is a magnetic type and the sensor is in the tank.

I should have enough fuel in the lines, filter, and motor to get me to the fuel station to put in about 15 gallons. I have a cruise to Dana Point in a few weeks.

 

[Stu Jackson]

We have a 23 gallon tank. As many of you know, I don't think fuel gauges are worth the cost 'cuz the senders keep going out. So, I keep records of fule fills and have determined that our engine uses less than 0.5 gph. Twenty hours, 10 gallons. I rarely let it go below half, not for any engineering reasons but simply 'cuz the fuel bill is too HIGH! Wouldn't show if someone siphoned my tank, though. Good luck, Brian. You could always get a jerry jug for a gallon or so before you tempt fate.

 

[Delezynski]

Stu,

I installed Wema fuel and water gauges in our tanks back in 98 or so. They have been working just fine ever since. The senders are a tube that slips into the tank and can be changed easy.

Fuel tank sender in photo, in the fuel tank clean out port;

I did have one (1) water tank (I have 2) sender hang up at full once. But as soon as I his a bit of rough water on a sail it jumped back to working just fine.

Greg

 

[Stu Jackson]

Greg, you're right. There are senders and then there are Senders. I was, of course, talking about the traditional float/rheostat el cheapo versions.

 

[finding41]

Brian have you given any thought to installing an anti siphon spring? I've seen them in car filler necks before. (Not when I was stealing gas. It's always too dark then. Lol.)
They kind of look like 1/2 of an egg beater spring stretched out. V shaped so the wide part of the V is at the top and it goes down about 8". (It's one of the reasons some cars don't like to take fuel with the nozzle at full power without clicking off.) It may take a bit longer to fill up with one inserted but with the price of fuel.... May as well get your $ worth at the marina fuel station.
Kind of like the one in the picture here. http://www.ebay.com/itm/2xDiesel-Fu...her_Vehicle_Parts&hash=item1c3624fda0&vxp=mtr

 

[Benny17441]

Look for a Perko Chromalex marine locking fuel cap. App $25 from online chandleries.

 

[Jon Bastien]

If the fuel filler hose is easily accessible from anywhere inside the boat, you could insert a 1.5" ball valve in the fill hose. Just open the valve when taking on fuel, and close it the rest of the time. The valve shouldn't restrict the flow of fuel when filling, and a thief wouldn't be able to get a siphon hose down that pipe.

Costs about the same as a locking cap, and doesn't come with a key you will lose in between your seasonal fill-ups...

(Google ' 1.5" Ball Valve Diesel ' by clicking here.)


Alternatively, you could install a pair of 90-degree elbows in the fill hose somewhere, making it extremely difficult for the thief to get his siphon hose through. Shouldn't restrict fuel flow at all, and requires no special effort on your part when it comes time to fill the tanks.

 

[Bill1565]

Greg, you're right. There are senders and then there are Senders. I was, of course, talking about the traditional float/rheostat el cheapo versions.

As far as I know, the float gauge/ dial in my tank is original, 1979 . Still works fine. Tank is odd shaped, but I filled it 5 gallons at a time from dry and wrote down gauge Readings
.

 

[rgranger]

Can't imagine anyone successfully siphoning from a boat fuel tank. mine is below the WL.

If it were stolen it may not have been siphoned but pumped. I had to empty the tank on my boat for some maintenance work and I purchased a small hand held fuel pump at Auto Zone. I then pumped the fuel into cans. It took about 20 min.

I think the $25 locking cap (that someone else has already suggested) makes the most sense.

 

[Anonymous 121765]

Brian,

Like the guys said, I would suspect the gauge. On my C30, I originally had a mechanical fuel reading gauge located on my tank. When I put in the new engine panel, I went with an electric one. They kept burning out or just failed. I put the original back on (1980). I fully emptied the tank, and each 6 gallon fill from a jerry tank, I took red fingernail polish (NOT MINE of course) and marked it. I did reset the float as close to exact as possible. I used the 6 GAL. fills until near tank top, each time marking them.

Yea, I have to lift the cover to check the level, however I know exactly how much fuel I have. Fuel consumption as small as it is, not too often.

CR

 

[Warren Milberg]

I guess it's a given that most criminals aren't the brightest lights on Broadway, but what kind of moron is going to trying stealing fuel from a small sailboat? My 2 cents here is that the fuel sender crapped out or you have a pin-hole leak in the tank or fuel lines. FWIW, I would never trust a boat fuel guage. I do what Stu does: know the consumption rate of your engine and keep a No. 2 pencil and spiral notebook handy to record actual usage. Has worked well for me for many years.

 

[Brian D]

I didn't have my tools with me yesterday. So tomorrow I will head back down and check the fuel gauge. Hard to check the sender unit but I will try. I will also add 5 gals of fuel and see if the gauge moves. I should see some reading.

Thanks for everyone's comments.

 

[jibes138]

If you had a leak the boat would reek of diesel fuel smell, you would also have a bilge full of diesel and possibly a reportable spill if the bilge pump came on and pumped it overboard. I debated putting in a gauge when I put in my new tank but since it is plastic I can see the fill level through the plastic, no more need for a gauge of any kind. My old tank had a mechanical gauge, it was a float on a helical metal rod that rotated as the float position changed. Very reliable and was still working fine at 28 years. I think I still have it if you think it would fit. Has a typical 6 screw configuration like a sending unit installation. Might be too long though.

 

[Ken13559]

We have a 23 gallon tank. As many of you know, I don't think fuel gauges are worth the cost 'cuz the senders keep going out. So, I keep records of fule fills and have determined that our engine uses less than 0.5 gph. Twenty hours, 10 gallons. I rarely let it go below half, not for any engineering reasons but simply 'cuz the fuel bill is too HIGH! Wouldn't show if someone siphoned my tank, though. Good luck, Brian. You could always get a jerry jug for a gallon or so before you tempt fate.

I've always thought of myself as an instrument person and yet when on passages, I naturally always calculate fuel consumption and check against physical level by sight. I've plastic tanks. My fuel gauge is working fine. Somehow my left hand column doesn't trust instruments on boats. Strange huh?

 

[justsomeguy]

Not strange at all.

 

[Ross]

Strangely but years ago I discovered that it didn't cost more to keep the tank full. Just install a hasp and padlock over the fill port.

 

[StinkBug]

Actually since fuel prices keep going up it actually costs less to fill up at the end of a trip and have it full for next time, rather than waiting to fill when you go out again.