Diesel Fuel Fill

Home or s/v Stella Blue Home or Deck Stuff or Projects

I'm going to put a new fitting on and
raise it up off the deck half an inch,
which might not be perfect but is a lot better than having it flush.

Fortunately, it's on a spot on deck
where you don't walk.

The pad is made from prefab fiberglass from McMaster-Carr, cut with a 4.5" hole saw and then beveled to a 45 degree edge with my bench belt sander.
To the right, you can see it with
the first coat of primer.

The old deck fitting was set in silicone.
It leaked into the stern area, though that
wasn't a real problem as it just ran down to the bilge. It will be good to seal it up right.

The deck is cored, and that was a big concern.
It was stained from water and damp because of the recent rain storm. However, since the fitting wasn't well caulked in the first place, there wasn't any sealant over the core and the water just ran right over it, and the surface was able to dry out quickly. It rained about three inches last week, and that's why it's damp.

The holes were a worry.

A lot of boats have the fuel fill right on deck, and so does Stella Blue.
An odd thing, though, is that it's also right by the deck drain. The result is that water flows over the Diesel fill, and during heavy rain or while washing the boat it's under water.

To the left, it's under 1/4 inch of water.
An O-Ring failure will let water into the fuel tank.

I cleaned all the old silicone off with my Handy Dremel tool, then reamed the core out.

The interior core was dry. Whew.

The hole itself is too big for the new fitting,
so I'm going to make an epoxy plug
for the entire thing, and seal the core as well.

The plug was made just like the one for the Windlass deck hole.

The new hole is solid, and the bolt holes have a small countersink to give a nice plug of caulk around the bolts.


I believe in using lots of caulk. It's cheap. When it gooshes out everywhere, you know you got it all over the place.

I taped off the inside of the deck fill, so it'll be clean when it's time to attach the hose.

The fiberglass pad
is painted dark Green,
for Diesel.

Don't forget to ground the fitting to the fuel tank, to meet ABYC specs. I have a wire from one of the bolts, that runs next to the fuel fill hose
down to the tank.


I put the camera away before washing the boat,
but this works great.

With the hose running full blast, the water flowed around the deck fitting and
didn't touch the top.

The fitting is branded by West Marine, so I don't know who makes it. I like it as it's
solid cast Stainless.