Bonding Diesel fuel fills

Here’s one for the bonding experts.
Just installed two new 170 gal. aluminum fuel tanks. Will it meet code If I bond the fuel fill to the bonding tab on the top of the tank and then bond the tank using the bonding tab on the lower front side of the tank?
Or should it run directly from the fuel fill to the bonding terminal ?

Why would you bond it at all?

My tanks are bonded to the transom grounding plate. Fuel fills aren't bonded and to the best of my knowledge aren't required to be for diesel.

Ted

ABYC A-33 requires it. Or at least it used to. Mainly for static electricity during filling as it is usually isolated by a rubber hose.

Northern Spy said:

ABYC A-33 requires it. Or at least it used to. Mainly for static electricity during filling as it is usually isolated by a rubber hose.

Click to expand...

Static electricity will ignite diesel as opposed to gasoline?

Ted

"Static electricity will ignite diesel as opposed to gasoline?"

A tank feeding an engine that uses fuel for cooling might be quite warm , with the fuel vaporizing in the tank.

A bonding wire should be less cost than a burger , so why experiment ?

FF said:

"Static electricity will ignite diesel as opposed to gasoline?"

A tank feeding an engine that uses fuel for cooling might be quite warm , with the fuel vaporizing in the tank.

A bonding wire should be less cost than a burger , so why experiment ?

Click to expand...

Don't think I've ever seen one before on a diesel boat. The fill pipes on my boat had no provision for attaching the wire. Wonder when the guideline changed.

Ted

From memory....



I too believe it is one of the few ABYC bonding hard lines. (fuel fills)


All bonding is best done to a central or nearly so buss bar....so daisy chaining is not recommended but I am not positive it is prohibited by ABYC.

We had a tool box talk at work that mentioned that the "new" ULSD has more static generating potential than the old diesel fuel.

We have retractable grounding cables at the fuel pumps at work that you connect to your vehicle before filling.

Our 40 year old diesel Mainship had the fills grounded by stripping the wire back, bending the bare cable over and into the end of the hose and the hose fastened to the fill with a clamp. I guess it satisfied the ground connection to the fill fitting and I never saw any evidence of leaking but what a dumb way to do it! When I reinstalled the fills after the deck replacement I just used an extra long machine screw for one of the 3 fasteners and attached the wire that way. Not one on Mainships better ideas.

Northern Spy said:

We had a tool box talk at work that mentioned that the "new" ULSD has more static generating potential than the old diesel fuel.

We have retractable grounding cables at the fuel pumps at work that you connect to your vehicle before filling.

Click to expand...

It is an OSHA and MSHA standard in the US for blasting rigs and ANFO trucks. Several lasting rig blowups around the world have been sparked by static electricity.

As time had marched on fuel delivery trucks were included. Given 500+ gallons of onboard fuel for many of us grounding the fills seems logical but is not rigorously followed by the USCG regs.

O C Diver said:

Static electricity will ignite diesel as opposed to gasoline?

Ted

Click to expand...

I've handled six insurance claims for boat fires caused by gasoline getting put into diesel boats. I've handled about another thirty insurance claims to get gasoline pumped out of diesel boats. ABYC requires it.

boatpoker said:

I've handled six insurance claims for boat fires caused by gasoline getting put into diesel boats. I've handled about another thirty insurance claims to get gasoline pumped out of diesel boats. ABYC requires it.

Click to expand...

Ok, got it.

The rule is designed to prevent "natural selection" from culling the boating gene pool.

Ted

Not really. Most people understand that diesel has a higher flashpoint than gasoline; 126F for diesel and -45F for gasoline. But, this is just a number, not an absolute value, as it will change from supplier and geographic location.

In the industry that makes diesel, often the safety threshold is set 20F lower to ensure a flammable vapour isn't present. (Reference API RP 2003.)

But what a lot of people don't understand is the Lower Explosive Limit (LEL) for diesel is only 0.6%. Lower than almost any other common flammable product. It takes a very small vapour volume in air to create an explosive mixture.

Flammable mists or foams can be created when filling which have an ignition point below that of the vapour flashpoint.

So it is precautionary, for sure, and not near as high risk as gasoline, but the consequences are exactly the same.

Certainly is prudent. You will find that most fuel fillers have a bonding lug to attach a wire.

Our 50 ft US Navy utility has a woven and tinned bonding wire from the deck fuel fill, past a 3 ft section of hose to the monel tank top.

Propnut said:

Here’s one for the bonding experts.
Just installed two new 170 gal. aluminum fuel tanks. Will it meet code If I bond the fuel fill to the bonding tab on the top of the tank and then bond the tank using the bonding tab on the lower front side of the tank?
Or should it run directly from the fuel fill to the bonding terminal ?

Click to expand...

who built your tanks I have 3 stock wood test tanks in the car . if the Moeller tanks don't fit I will consider custom tanks .