Metal tab on top of fuel tank???

This may sound like a silly question but I have to ask.

I have an older (1998) Sportcraft Fishmaster 180 with an aluminum RDS Manufacturing, 60 gallon fuel tank. My fuel guage stopped working so I checked the wiring at the sender. The ground wire was detached due to age and vibration over time. It appears to be the original wiring and connection. I have reviewed other fuel sender postings on this site and I have also looked at instructions on the Moeller website to make sure I am connecting things properly to avoid problems due to the close proximity of the wiring to fuel and possibly vapors.

All of the information I have found so far tells me that the ground wire should be attached to one of the screws holding the sender to the tank. I noticed a metal tab on the top of my aluminum tank and would like to know if this could also be used, or was intended to beused, as a grounding point.

The guts of my boat are opened up and I don't want to wait until Monday when I could call RDS to ask them. Does anyone know what this metal tab is for?

Thank you!

Re: Metal tab on top of fuel tank???

Does the metal tab look like a standard electrical spade terminal? If so, then yes...it can be used also. Either a spade terminal on the tab or a ring terminal on the fuel sender unit are fine.

Re: Metal tab on top of fuel tank???

It's not a terminal but has a hole in it that appears to be original and not the work of someone after it was manufactured. This is why I was curious as to whether or not it could be used as a grounding point.

Please see attached picture.

Re: Metal tab on top of fuel tank???

Is there another tab similar to that on the other side of the tank. That looks to me more like a lifting eye for handling the tank during installation.

Re: Metal tab on top of fuel tank???

dwco5051 said:

Is there another tab similar to that on the other side of the tank. That looks to me more like a lifting eye for handling the tank during installation.

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There does not appear to be from my limited point of view leaning over the back hatch, contorting with a flashlight. If I ever design my own boat, there will be access panels and quick release fittings for everything! Much like cars, they are designed to be assembled, not repaired.

I came up with a temporary fix until I can research this a little more or decide to just replace the fuel sender.

Thank you for your help!

Re: Metal tab on top of fuel tank???

That tab could have been a grounding point during construction of the tank. If there is not a hole in it, then you would have to drill it to use it as a ground. Use the fuel sender screw for the ground.

Re: Metal tab on top of fuel tank???

I have dual RDS tanks in my boat. The angle welded to the tank with a small hole (~3/16") is the fuel tank ground. Fuel fills and senders are to be grounded to this point.

FWIW: You should never use threaded fasteners as grounding point, especially when dissimilar metals involved. Ground connections should be thru bolted if at all possible

Re: Metal tab on top of fuel tank???

dingbat said:

FWIW: You should never use threaded fasteners as grounding point, especially when dissimilar metals involved.

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???????? Threaded fasteners are used as grounds on 95% of all applications! Guages, buss bars, fuel senders, grounding straps, etc.

Re: Metal tab on top of fuel tank???

i think dingbat meant nut bolt fasteners versus self tapping screws which are more prone to corrosion

Re: Metal tab on top of fuel tank???

Mine has a green wire with crimped ring eye on the angle and two wires going to the removeable sending unit +VDC on isolated stud and female insulated connector to ground . Might be safety from static voltages ?

Re: Metal tab on top of fuel tank???

The tab is both static ground, and electrical ground.
Some fuel gauge senders do not ground through the mounting screws. So instead of running separate wires to ground, there is a tab designed into the tank that is grounded.
The static part also included the metal fuel fill fitting on the boat, which is connected by hose to the tank. To prevent static the fuel fill fitting is grounded to the tank, on that tab.
99% of those tabs have a self taping screw in them.

Re: Metal tab on top of fuel tank???

vxtech said:

i think dingbat meant nut bolt fasteners versus self tapping screws which are more prone to corrosion

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Thru-bolt = nut + screw, preferably, Nyloc nut.

Self tapping screws have no place on a boat, or anyplace else where vibration is an issue.