Fuel sending unit leaking

[Donaldpeter]

Hello, I own a Newport 28 MK II 1985 sail boat. I've filled my fuel tank up too far and the fuel sending unit is now leaking diesel fuel. My tank is plastic and the fuel sending unit has 5 phillips(+) pan head metal screws and a large rubber washer with 5 holes in it located between the sending unit and the plastic tank. The return wire is under one of these screws. This clearly doesn't seal fuel comming up the screw threads and leaking around the screw heads with a full tank. Can any one tell me if this is normal for my boat or if its the work of the previous owner and what the configuration should look like for a plastic tank. Also is there an easy way to drop the fuel level in my tank so I can do the proper repair. Thanks Pete

[LakeSuperiorGeezer]

You could tie the boat securely to the dock, start the engine and put it in gear, advance the throttle a bit for added fuel consumption and burn some of the diesel off. You could also call an auto parts store, tell them the problem, and get a siphoning setup to move diesel to a separate container. An automobile parts store would also know the proper sealant for diesel gaskets.

[ok5597]

I have the same problem. I overfilled the fuel tank and the screws on the top of the sending unit are leaking. It seems that the leak would occur when fuel is sloshing around underway anyway, so siphoning out fuel isn't really a solution. Have you found a solution?

M

[tommays]

Thread sealent for fuel

[rikhall]

One little thing I did that might help in the future (or might help others before it happens) is that with the tank as empty as possible, I poured in 5 gallons, marked the fuel gauge with a sharpie, poured in five more, marked it with a sharpie, and repeated until just about full.

By looking at the fuel gauge, I now know, for a fact, how much it can take without over filling.

I also know how much is left in the tank for planning purposes.

This tip came from my friend Mike when we were setting up our boat from two boats ago.

Rik

[Donaldpeter]

The way I solved the issue was to first drain 5 gallons from the tank by disconnecting the fuel feed hose from the fuel pump and running it to a fuel tank in front of the engine. I then removed the fuel sending unit and cleaned it, the screw holes, the tank interface, and the screws with Simple Green and a clean rag. I installed a new gasket and used permatex #2 on both sides of the gasket and on the screw threads and screw threaded holes in the tank. I assembled using my calibrated hand for proper torque. I also sprayed and poured simple green where the diesel fuel leaked and let it run into the bilge. I have a solar fan that vent through the hatch. It took about a month for the smell to dissipate. If you have screws that thread into a plastic tank like I did you might want to reevaluate permatex #2. There may be a better sealant.