Adding a Fuel Bladder -- grounding

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quantase

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Hello all. I plan to add a fuel bladder for extended range when fishing on my single engine. I plan to do a SS quick connect system and plumb the bladder to my water separator. I would have a SS ball valve for the bladder and one for the boat's gas tank. I want to ground the SS ball valves (they have a small nut for grounding) to decrease chance of static. Has anyone done this that can share with me how they protected from potential static that could cause a spark. Where do I ground the ball valve on my boat? I have heard mixed comments of running a 14g green wire from both ball valves to the negative post on my starter or house battery. Not sure if that is the best or safest? Any thoughts on where to ground? For those of you who have done this, please share pics of your setup. That would be helpful. Thanks.
 
I suggest you contact the manufacturer of the bladder you would use and ask for advice. I suspect that no protection is needed. Grounding and bonding are different systems with bonding usually dedicated to galvanic activity. Incorrectly connecting the two together as well as incorrect bonding feeds can result in serious electrolysis conditions. Using a motor ( like the starter) as a ground source can result in damaging ground currents or circular currents, both of which can cause serious damage.


Static sparks are more an issue in the presence of fuel vapors similar to those possible when fueling at the fuel dock and not so much from just motoring.

My advice is to not wear silk underwear:)
 
Thanks for the suggestion. I would use an ATL Fuel locker bladder with SS valves and fittings. Yes, maybe I’m overthinking it, but I hear that static can generate as fuel is going through the SS quick connect fittings.

I guess those Silk underwear will need to go into rotation.
 
Someone correct me if I'm not thinking of this correctly or missing something... the only way a spark would be created is if something metal touches the valve - such as when filling a gas tank with the fuel nozzle - which won't happen here.
 
I believe a spark can come from stray static. Brush against clothes enough, one can make a static charge.
 
quantase said:
I believe a spark can come from stray static. Brush against clothes enough, one can make a static charge.
Click to expand...
Hmm. Well, you're right. But that would mean YOU would be carrying the charge. Although I thought that only happened when you were standing in a line in the library on a carpeted floor and you drug your feet back and forth on the carpet and then touched the earlobe of your friend in front of you.........

OK, so thinking through this more... let's say a charge was built up on the fitting or on you. Wouldn't the spark still be on the OUTSIDE of the fitting? There should be no vapors on the outside... note I said "should" - in cases like this, it's probably best to err on the side of caution :)

So... regardless of the answer... and since I admittedly don't know the absolute correct answer... it certainly can't hurt to ground it.

I would use a negative bus bar with a permanently attached lead. Leave the other end of the lead in a convenient, but stowable location. Use a quick-disconnect fitting on the end that matches the end of the grounding wire from the fitting. Something simple like a bullet connector would be fine.
 
The small nut you mention is for bonding, not grounding. If you vessel does not have a bonding system installed, fittings should not be connected to battery grounds. The probability of a static spark is generally low since the humidity has a lot to do with static electricity buildup ( on your body) . In addition, gasoline in itself, is not explosive, gasoline and air mixture is. The fuel take off of the bladder is less likely to be a concern than the bladder vent.
 
My fuel fills were both grounded (green wire). No photo but I remember them being a pain to get on. The tanks too. Not sure what that green wire connects to (battery ground???). No visible ground on fuel valve photo but I'll check.

I don't like the idea of running off of the bladder. If it were me I would transfer into boats tank. Generally I don't like the idea of a gasoline bladder at all!
 

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Hookup1 said:
My fuel fills were both grounded (green wire). No photo but I remember them being a pain to get on. The tanks too. Not sure what that green wire connects to (battery ground???). No visible ground on fuel valve photo but I'll check.

I don't like the idea of running off of the bladder. If it were me I would transfer into boats tank. Generally I don't like the idea of a gasoline bladder at all!
Click to expand...
Does you boat have a shore power system? If so, is there a galvanic isolator?
 
seasick said:
Does you boat have a shore power system? If so, is there a galvanic isolator?
Click to expand...
No, I do not have shore power on my vessel. It has a two bank battery charger (starter & house). There seems to be a ground wire coming from my fuel tank and going to the negative terminal of my battery. Any issues if I connect both of my valves together with a 10awg and route them to the negative terminal on one of my batteries?
 
There won't be any issues by doing that - I think we're still just wondering if it's necessary. But as noted a few times, there's nothing wrong/dangerous about doing it. You won't need 10g - although, again, it can't hurt.

As noted above, best practice is to go to a bus bar. Going right to the battery is OK, though.
 
The tank ground is there to prove the negative return part for the fuel sender to work. It is not there to control static.
I don't see a need to ground the fuel valves. Improper grounding can cause damage to components
I should also point out that a bladder is an insulated device and is no different than a poly gas tank. Those are not grounded. I would be more concerned about the inherent risks with portable bladders .especially with respect to movement and vibration.
 
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