Question about refueling

[krafty81]

Second time I have put diesel in my boat. First time they topped it off no problem. Today, I was down to about half a tank. They started pumping, and less than a minute later, fuel started coming out of the weephole. I assumed the tank was full and my wife paid the bill. After we left the dock (of course) I noticed they had only put in three gallons and my tank went from half to three quarters. Not full. Has this happened to anyone else. I believe the gauge is correct.

[Noah]

The "expertise" and patience of the person on the fill nozzle and the speed at which they fill it, can impact the perception of how truly full the tank is. I recommend, in the future, you keep a good record of engine hours run and calculate fuel burned between fill-ups that way. The gauge may be somewhat accurate but since the tank is not square, it does not give you a true linear measurement from empty to full.

[krafty81]

The "expertise" and patience of the person on the fill nozzle and the speed at which they fill it, can impact the perception of how truly full the tank is. I recommend, in the future, you keep a good record of engine hours run and calculate fuel burned between fill-ups that way. The gauge may be somewhat accurate but since the tank is not square, it does not give you a true linear measurement from empty to full.

It showed full the last time I filled it. So I think that works. Also, based on hours that I track, I burned more than three gallons.

[Jim Hardesty]

I assumed the tank was full and my wife paid the bill. After we left the dock (of course) I noticed they had only put in three gallons and my tank went from half to three quarters. Not full. Has this happened to anyone else. I believe the gauge is correct.

Shamrock does have a working fuel gage but that's not what I depend on.  Like many here I use the hour meter and fuel consumption.  That way I know how much fuel to take on.  Shamrock should be similar fuel usage .7 gph that would be a good start for you.  In the log I keep track of hours, fuel and where I got the fuel.  I'm a little paranoid about getting clean fuel.  Also I put a small whiteboard by the nav station.  I write down the hour meter reading at last fill up. 
Jim

[scgunner]

krafty,

You may have gotten a "boil up", diesel can get foamy if filled too fast. Think of a beer poured too fast with a big head on it, when it dissipates your glass isn't full. When fueling at the dock you should slow down the flow as you approach the top of the tank. Does somebody else fuel your boat at the the fuel dock? When you say weep hole are you talking about the over fill line that runs to the transom? Did it spill into the water? That's a BIG no-no!

I no longer fuel at the fuel dock instead I use a 6gal yellow plastic fuel container. That allows me to check the purity of the fuel and measure additives more precisely. Also to prevent the possibility of overboard spill which could result in thousands of dollars in fines I've routed that overflow line to a two gallon gas can located in the transom locker.

[krafty81]

krafty,

You may have gotten a "boil up", diesel can get foamy if filled too fast. Think of a beer poured too fast with a big head on it, when it dissipates your glass isn't full. When fueling at the dock you should slow down the flow as you approach the top of the tank. Does somebody else fuel your boat at the the fuel dock? When you say weep hole are you talking about the over fill line that runs to the transom? Did it spill into the water? That's a BIG no-no!

I no longer fuel at the fuel dock instead I use a 6gal yellow plastic fuel container. That allows me to check the purity of the fuel and measure additives more precisely. Also to prevent the possibility of overboard spill which could result in thousands of dollars in fines I've routed that overflow line to a two gallon gas can located in the transom locker.

No it did not go overboard. I use a rag at the weephole to ensure that does not happen as I am sure others do. I think you are correct that it was probably filled to fast and bubbled over somehow. Just wondering if that has happened to someone else. I will go back to the fuel dock and see what I can get from them.

[Kyle Ewing]

I have to fill it slowly or it will spray out the vent before it's full. I always have someone watch the vent with a rag and I watch the fuel guage. I slow it down to a trickle when close to full

The pumps where I fill are high volume designed to fill tanks with 100s of gallons of fuel. The foam theory makes sense combined with the small vent.

[Ron Hill]

Krafty & Guys: If the fuel dock hand gives you a fuel nozzle that will NOT fit in the C34 fuel fill - you have a nozzle to a high speed fuel pump - which you do not want!!!

When that happens to me, I ask the dock hand if he has a low speed diesel pump - which they usually do have!! Then the fuel nozzle fits in the C34 fuel fill and all is OK!!

A few thoughts