Grounding Gas Deck Fill

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PaulKim

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I just purchased a underdeck tempo gas tank. 18gals. I would like to install a stainless steel Gas Deck fill, but it appears that I need to ground it. I wasn't sure if I can just ground to the battery negative. <br />Searched this forum, and couldn't find any answers specific, besides bonding.<br /><br />Thanks
 
Bondo

Bondo

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Re: Grounding Gas Deck Fill

The Gas Fill should be bonded to the Gas Tank,..<br /> <br />Which should be bonded to the Engine Block......<br /><br />Which in turn is Grounded to the Battery Negative post........
 
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surlyjoe

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Re: Grounding Gas Deck Fill

and if its an inboard, ground the shaft and strut too!
 
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mulv80

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Re: Grounding Gas Deck Fill

How does the tank get grounded to the engine block on an outboard?
 
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epresutti

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Re: Grounding Gas Deck Fill

mulv80,<br /><br />Like Bondo said, everything eventually returns to the negative terminal. Unless there is voltage "leak" into the water somewhere. Electricity (DC) will flow from positive to negative. There is usually a large black 6 gauge or bigger ground connected to the motor somewhere.<br /><br />I don't see a difference between a connection to the negative terminal or to the block. Is there?<br /><br />Peace.<br /><br />Ed.
 
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PaulKim

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Re: Grounding Gas Deck Fill

So, I'm assuming that bonding means connecting it to the next item in the line.<br /><br />For Example: Connect Fuel deck to the Engine Block, which then would be connected to the negative terminal on the battery.<br /><br />If that is correct, can I just connect the fill deck to the negative terminal on the battery?
 
MRS

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Re: Grounding Gas Deck Fill

No your tank should have a ground post run wire from filler to gas tank ground post to engine block.
 
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epresutti

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Re: Grounding Gas Deck Fill

MRS, et. al.<br /><br />I don't completely understand.<br /><br />Why to the block? <br /><br />Is the goal eventually to get it into the water or to the anode? <br /><br />Is this a safety issue, if the battery switch is turned off or disconnected?<br /><br />Does the block act like a big resistor? <br /><br />Does anyone know the electronic theory/workings on this?<br /><br />I will be doing the same thing shortly on my rebuild.<br /><br />Peace.<br /><br />Ed.
 
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mulv80

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Re: Grounding Gas Deck Fill

This is the way I have since been told how to ground the tank. Run a grounding wire from the fuel fill to a tab on the tank, next run a wire from the same tab to the negative post of your battery, then run the ground for the fuel sending unit to where the other gauges are grounded. Does this sound right?
 
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rodbolt

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Re: Grounding Gas Deck Fill

bonding wires are green and ground wires are black. there are a few rules for bonding and you can find them on the net.<br /> the basic for your deck fill will be fill to tank and tank to negative battery post. if the block is easier go to the engine block. the idea is to hold(bond) all metal parts of the hull that may be susceptiblew to static charges to the same potential.<br /> imagine this. the deck fill is a mettalic conductor surrounded by an insulator so it can have a triboelectric charge(static electricity) now place the nozzle on the charged deck fill and as the nozzle is at an earth ground potential you can get a static spark of 20Kvolts or more. in other words you just created a sparkplug in your deck fill.<br />so the USCG says any mettalic deck fills must be electrically bonded to the hulls negative system which also includes the engine block. also fuel flowing throgh the fill can produce static charges as well.<br /> static lectricity does funny things and can even make your spouse jiggy after a good zap :) :) .
 
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PaulKim

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Re: Grounding Gas Deck Fill

This is scary stuff. Would hate to be filling up my tank, and kabooooom there goes my boat, my hand and probably my head. Kinda makes want to use a plastic deck fill :(
 
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PaulKim

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Re: Grounding Gas Deck Fill

Thanks everyone. I'm almost there.<br /><br />In looking at the back of my Guel gauge it appears that there is a ground. <br /><br />My approach is as follows<br /><br />Bond Deck Fill to Gas Tank, Gas Tank to Fuel Gauge (Black Ground), Fuel Gauge to Tach, Tach to Control, where the control is bonded to the Outboard, and control is grounded to negative battery terminal.<br /><br />Will this work, or should I increase my life insurance :)
 
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samsam

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Re: Grounding Gas Deck Fill

Originally posted by PaulKim:<br /> Thanks everyone. I'm almost there.<br /><br />In looking at the back of my Guel gauge it appears that there is a ground. <br /><br />My approach is as follows<br /><br />Bond Deck Fill to Gas Tank, Gas Tank to Fuel Gauge (Black Ground), Fuel Gauge to Tach, Tach to Control, where the control is bonded to the Outboard, and control is grounded to negative battery terminal.<br /><br />Will this work, or should I increase my life insurance :)
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I don't understand electricity as well as I would like, but to be on the safe side, let me add some negative (pun intended) thoughts. In the above scheme it would seem that disconnecting any of the above links would leave the fuels system ungrounded, ripe for a static explosion. In most of the other systems proposed, if the battery is disconnected the same situation would be created. I believe I have noticed, especially on the bigger boats, a copper grounding strap running the length of the boat that EVERYTHING is grounded to, which strap in turn is permanantly grounded to an unmoving (not the propellor shaft, etc) underwater part, such as a bolt that directly connects to the propellor shaft strut or a sintered copper plate. This is in addition to all the negative electrical wiring that runs back to the battery. This is to insure the discharge of static electricity at all times, even when the battery is disconnected or the motor is taken out. I believe that the negative side of wiring and the grounding of electricity are not the same thing, if that makes any sense.<br /> Sort of off topic but relating to sintered copper plates (which are plates attached to the bottom of the hull made from thousands of tiny copper balls fused together that offer a huge amount of surface area, compared to a solid plate, for grounding purposes), if you have lightening protection on your boat and it is grounded to one of these plates, if lightening hits, it immediately turns all the water in the spaces between the copper balls into steam which cannot readily escape so the plate explodes, sometimes putting a huge hole in the bottom of your boat. <br />Yes, increase your life insurance. Sam
 
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rodbolt

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Re: Grounding Gas Deck Fill

the operational grond wires for any circuits MUST be seperate from the bonding wires. your not supposed to use the bonding wiring for operational circuits. thats what ground wireing is for. I saw it all the time in AC house wiring where the Nuetral would fail and someone would shift the nuetral to the ground. it can create an issue.<br /> will it work as you describe? most likly, but its not what the ABYC,BIA and USCG desire.<br />whats even funnier are the amount of fuel senders that are not bonded to the fuel tank. the only bond they have is that staple in the rubber gasket that corrodes away in the first 6 months.<br />some riggers actually use that staple as the ground path for the fuel sender. <br /> its crazy but it keeps me in minnows and horse feed.
 
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epresutti

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Re: Grounding Gas Deck Fill

Guys,<br /><br />Like samsam said there are a few more things to consider. I found this: Marine Grounding Systems <br /><br />Which gives an excellent description of the various types of grounding, including AC/DC, Antenna, and RF ground. It was produced by West Marine Advisors.<br /><br />I plan on following their recommendations.<br /><br />Peace.<br /><br />emp.
 
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samsam

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Re: Grounding Gas Deck Fill

Originally posted by rodbolt:<br /> the operational ground wires for any circuits MUST be seperate from the bonding wires. your not supposed to use the bonding wiring for operational circuits. thats what ground wireing is for. will it work as you describe? most likly, but its not what the ABYC,BIA and USCG desire.<br />
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I think it also sets everything up for galloping galvanic corrosion. Sam
 
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