Filling gas tank from inside the locker?

[tomlarkin]

I'm installing a gas tank and trying to decide the best place to have the deck fill. I think I'll make a small well inside the stern locker, as below. The locker itself is well-ventilated.

Here's why I want to do this:

• It’s lockable - 25 gallons of gas is becoming a real investment
• The hardware is out of the weather so it should last longer
• One fewer thing on deck to stub your toe on
• The tray will catch any drips so you can dispose of them correctly. It's unlikely that you could spill gas into the boat or the water.

Any objections to this idea? I've never seen it done this way.

[Lew Barrett]

You haven't seen it done because gasoline fumes are heavier than air and thus they will settle in the bilge. Then again, it's illegal to put your deck fill inside the boat, so that could be another reason. Put it on the deck, and fulfill the promise of a "deck fill."

[The Bigfella]

Tom - I've done something similar - but not with "gas" - only with diesel.

My fill points are going inside a step that goes from the deck up to my sundeck - but it still classifies as a deck fill because it is essentially just a deck fill that is raised 10" or so above deck level and is in a ventilated step space. The steps on my boat will be ventilated at the bottom - which is where any fumes would gather - and they can't go into the bilge because the deck still exists under the step.

The risks associated with what you are proposing are huge and any attempt to ameliorate them (eg bilge blowers) are a bit like putting bandaids on a severed arm.

[jerry bark]

I'll only add that the overflow must be placed below the sheerline on the outside of the boat. also, since your boat is not metal you will need to have a ground wire that connects the deck fill to the gas tank.

West Marine sells locking gas caps that fit most common deck fills if you need one. they also have several types of vent line devices that are intended to help prevent you from overfilling the tank and spilling gas into the water.

cheers
jerry

[Woxbox]

One more thought -- you want the rim of the fill itself raised so that water and crud can't collect around it and fall into the tank when you remove the cap.
I have two diesel tanks under a cockpit seat, but I wouldn't do that with gas myself.

[boylesboats]

start that engine with a fumes build ups... KABOOM!

[The Bigfella]

No need to start the engine for that to happen with fumes in there. Any electrical switching would do it.

Make sure that even with a deck fill, when filling there are no open hatches for fumes to go down.

[tomlarkin]

KABOOM!

Geez guys, don't beat around the bush!

I'm convinced - it's going on the deck where it belongs. Thanks for the unequivocal feedback.

[Lew Barrett]

Tom, it is delightful to give a guy the bad news and have him respond with the right answer. I'll keep an eye peeled for you. What will you name your Devlin?

[kc8pql]

Tom, it is delightful to give a guy the bad news and have him respond with the right answer.

Ditto

[jollymon]

Glad you decided not to join the BIG BANG club!!

[tomlarkin]

What will you name your Devlin?

My working name for the boat is 'Donut'. Nothing goes better in the morning with a cup of coffee than a donut .

It's been a great project so far. I've asked this group a number of questions and always gotten thoughtful, well-reasoned answers. There are just a lot of things a complete amateur runs into on a task this large, especially since I'm not following the plans very closely. I ask Sam Devlin the occasional question (and he always answers), but I don't think that buying $300 worth of plans entitles me to very much of his time.

Expect more off-the-wall questions!

[banjoman]

also, since your boat is not metal you will need to have a ground wire that connects the deck fill to the gas tank.
jerry

Any need to ground the tank (stainless) to anything? We have been trying to figure out how to properly ground the fuel system on Starduster. The filler is grounded to the tank but the tank isn't grounded to anything.

[SchoonerRat]

Any need to ground the tank (stainless) to anything? We have been trying to figure out how to properly ground the fuel system on Starduster. The filler is grounded to the tank but the tank isn't grounded to anything.

If the tank isn't grounded than there is no ground! The easiest thing to do is connect the tank or filler to your thru-hull bonding system.

[tomlarkin]

The easiest thing to do is connect the tank or filler to your thru-hull bonding system.

I don't have any through-hulls on this boat. Can I run a ground to one of the outboard mount bolts?

[SchoonerRat]

Not sure a mounting bolt for o/b would do it. Shock mounts probably isolate the motor from the mount. If you have a 12v system, a connection to the battery ground should do it. This is a little out of my expertise. I've never dealt with a built in tank with o/b.

[Larks]

Nice project Cuz', and great blog. It's good to see another Larkin mad enough to play with wooden boats...must be an Irish thing.
cheers
Greg

[Woxbox]

How about a little thread drift?

If the boat isn't grounded, what's the risk from lightning? Do you ignore it in a smaller powerboat? Or should all boats that will be out on open water have some sort of mast and lightning protection?

I've always put a lightning ground on any boat I've slept in.

[Wooden Boat Fittings]

Tom, it is delightful to give a guy the bad news and have him respond with the right answer. I'll keep an eye peeled for you. What will you name your Devlin?

I totally agree with Lew.

As Bob said on the "Rating The Experts" thread, "Free advice is worth what you pay for it and its price is gratitude.... Few are experts on everything, but many are experts on a few things. If you want to know who the experts are, shut up and listen."

Tom said above, "I've asked this group a number of questions and always gotten thoughtful, well-reasoned answers." This demonstrates that he's one of the ever-dwindling number who listen to and are grateful for the advice they've asked for, which in turn makes him one of the relatively few who I'd now bother to advise, were he asking about something within my field of expertise.

Congratulations and the best of luck with your project, Tom.

Mike

[willmarsh3]

Not sure a mounting bolt for o/b would do it. Shock mounts probably isolate the motor from the mount. If you have a 12v system, a connection to the battery ground should do it. This is a little out of my expertise. I've never dealt with a built in tank with o/b.

When I had my Catalina 25 it had an outboard with an inboard tank. But the tank was removeable. Safety rules in that case mandated that I remove the tank to the dock to refuel. Only after I added the oil and put the cap back on did I put it back in the boat and hook it up. There was no grounding wire connected to the tank.

I think the ABYC would cover this.

[C. Ross]

If you have a 12v system, a connection to the battery ground should do it. This is a little out of my expertise.

I disagree SchoonerRat, but someone like Paladin or Tylerdurden or Crawdaddy Jim trumps either of us!

Returning a circuit to the DC neutral only completes the circuit. It will not provide a ground against static charge created from gas flowing into the tank.

You say you have no thru-hulls, but if you've got a gas tank you must have an engine, which must connect to a prop shaft and propeller. If you ground the whole system, including the bonding wire from the gas tank, to the engine block, you've grounded it.

(If you're in Seattle I assume you're in salt water. I knows nuthin about what you need to do to avoid corrosion from stray charges and galvanic action in salt water....others can add here...)

[skuthorp]

I've seen flwxible waterproof covers that fit over the filler too, are those legal over there?
Like the name 'Donut', good for a wooden boat too, it's got a hole in the middle that you can throw money in without ever filling it up.

[SchoonerRat]

I disagree SchoonerRat, but someone like Paladin or Tylerdurden or Crawdaddy Jim trumps either of us!

Returning a circuit to the DC neutral only completes the circuit. It will not provide a ground against static charge created from gas flowing into the tank.

You say you have no thru-hulls, but if you've got a gas tank you must have an engine, which must connect to a prop shaft and propeller. If you ground the whole system, including the bonding wire from the gas tank, to the engine block, you've grounded it.

(If you're in Seattle I assume you're in salt water. I knows nuthin about what you need to do to avoid corrosion from stray charges and galvanic action in salt water....others can add here...)

In the absence of metal in the water to bond to (this is an outboard) I'm not certain if connecting to battery ground will help (sorry I didn't make that clear in my post), but it sure seems to me that a connection to battery ground would give the static charge a place to go that wouldn't cause a spark.

How about a comment from somebody with more brains than me.

[SchoonerRat]

BTW, when you connect to your engine block, you are, in effect, connecting to battery ground.

[C. Ross]

Here's an old article on marine grounding systems that might be helpful.
http://www.sailmail.com/grounds.htm

SchoonerRat I think you're right. Since the battery neutral is going to be connected to the outboard block anyway for the spark plug and alternator, maybe that's enough grounding. I just think it's important to point out that you can't ground static into a DC battery neutral ALONE . You still need some kind of earth ground into the water via the outboard or an inboard prop shaft.

Hey, where's a qualified electrician when you need one?

[SchoonerRat]

Hey, where's a qualified electrician when you need one?

I sorta figured that without the earth ground there might be a problem, but it still seems that even just a battery connection might alleviate the possibility of sparking at the fill. A solution in this case might be to have a big hunk of metal on a 8 or 10 guage wire that could be temporarily connected to the fill and dangled in the water during fueling.

[C. Ross]

Exactly. Like gas tanker trucks that drop a ground wire when they fill or empty at a gas station. Could do it. We need an outboard electrician!

[tomlarkin]

I found the USCG site that answers some of these questions, including my original one. It's surprisingly well-written. I'm still somewhat confused as to how and where to ground the tank though. And how do I know if my electrical connections in the space are 'ignition protected'?

Rule 183-564: Each fuel fill opening must be located so that a gasoline overflow of up to five gallons per minute for at least five seconds will not enter the boat when the boat is in its static floating position. (Answers my original question pretty clearly!)

Rule 183-572: Each metallic component of the fuel fill system and fuel tank which is in contact with fuel must be statically grounded so that the resistance between the ground and each metallic component of the fuel fill system and fuel tank is less than 100 ohms.

Rule 183-620-a3: A compartment containing a fuel tank that is permanently installed, as opposed to a portable tank or container, does not require natural ventilation unless the compartment contains an electrical component that is not ignition protected.

Rule 183-620-a4: This section on fuel tank vents requires that vents have a flame arrester and not allow a fuel overflow at the rate of up to two gallons per minute to enter the boat. This requires a fuel tank vent opening that is outside of the boat and will not vent into the compartment.

[pila]

We had a guy blow his boat apart around here some years (8 or 10) ago. He didn't use the blower after fueling up, and got blew clean off the stern and into the water, and dropped the can of beer he was holding. It gets better with his next boat, but that's another story.