Unconventional Deck Fuel Fill Installation and Bed-It Tape

[sailcapt340]

When using Bed-It Tape to install a Deck Fuel Fill, do I use the supplied Fuel Fill rubber gasket with the tape or just the Bed-it Tape alone?
This is a different sort of installation……
What I am doing is installing a 2” stainless steel deck fuel fill with approximately a 3“ long neck into a generator enclosure at my home.
I am using this as a pass through access for a 3/4” Natural Gas Hose to feed the generator. No hose will be attached to the fuel fill neck, its just access into the enclosure when needed.

The nature of the 3/4” Natural Gas hose is so wide and thick it will not bend into a tight corner. It can curve perfectly but just not bend.
So the 2” Fuel Fill inside diameter opening is wide enough to pass the hose through with the Quick Connect fitting attached and I end up with a straight run from my home supply directly onto my generators intake.

The aluminum wall it is going to be mounted to is just over 1/8” thick, with a lightly textured finish.
And it is being mounted Horizontally and through bolted. Not screws.
I ask because I want a weather tight seal.
Thank you in advance for your help.

 

[Stu Jackson]

Your second picture shows that the edge of the stainless metal is wider than the rubber gasket. If you kept the gasket, there would be a gap. I would remove the gasket. You also need to use (much) more than one layer of bed It. I would take "gobs" of it (gobs = technical term for lots!) and roll it into lengths so you can deal with the appropriate thickness, and then wrap it around the tube, against the ss flange and the wall. Bolting is a very good idea and actually required for Bed It. I have re bedded deck hardware successfully with Bed It.

 

[thinwater]

You do not use bed-it (butyl) with fuel or gasoline. It will dissolve if there is a spill. The most fuel-resistant of marine sealants is silicone, but polyurethane is pretty good. But not butyl, unless you will never, ever have a spill, dribble, or drip. Butyl rubber is never used for fuel gaskets either.

Google it.

Bed-it Tape is good stuff. I have had good experiences with butyl tape for 40 years, staying within its limits. I had some bad experiences early on, when I used it for the wrong things. It is NOT magic. You still need polyurethane and silicone sealants, the best choice depending on the job at hand.

 

[sailcapt340]

You do not use bed-it (butyl) with fuel or gasoline. It will dissolve if there is a spill.

I agree completely. Great advice when planning to install a Fuel Fill and use it as one.
But for my use I can guarantee it will never see gasoline or diesel. As it is strictly used as a pass through access for a Natural Gas hose. Which leads me to another question….

You still need polyurethane and silicone sealants,

As I am applying the Bed-It Tape to the flange edge and outside wall. I will still need to use a silicone sealant on the inside edge as well to complete the seal when I bolt it in place?

I would take "gobs" of it (gobs = technical term for lots!

I have a niece who would translate this for me and say Lots and Lots.

Thank you again.

 

[Stu Jackson]

I will still need to use a silicone sealant on the inside edge as well to complete the seal when I bolt it in place?

Why? I don't understand the geometry. As long as the niece's lots & lots are there, what is left to seal? Wall>>Bed It>>flange No other sealant needed.

 

[rgranger]

You do not use bed-it (butyl) with fuel or gasoline. It will dissolve ....

 

[jssailem]

I am using this as a pass through access for a 3/4” Natural Gas Hose to feed the generator.

This is the operative condition for this query. The Deck Fill unit will not be subjected to a liquid. A hose for LNG or Propane appears to be used to move the fuel source of the "Home generator" from outside to inside his home.

I would say the use of Bed-it as a caulking around the deck fill would be more than adequate as a waterproof caulking. It would stop water from gaining ingress around the edges of the deck fill unit.

 

[thinwater]

... As I am applying the Bed-It Tape to the flange edge and outside wall. I will still need to use a silicone sealant on the inside edge as well to complete the seal when I bolt it in place?...

If it is through-bolted, butyl should be all the sealant you need. Clean up the squeeze-out with a plastic knife or similar.

It is NOT typical to seal inside the hull; if there is a leak, on any fitting, you want it to drip through rather than trap moisture where it should not be. I also think I'm not clear on the "inside edge" terminology.

 

[kappykaplan]

It is NOT typical to seal inside the hull; if there is a leak, on any fitting, you want it to drip through rather than trap moisture where it should not be. I also think I'm not clear on the "inside edge" terminology.

This is on his house, not his boat.

 

[thinwater]

This is on his house, not his boat.

Good point. On weather surfaces, the same principle applies. You do not want water hiding inside the wall. Better that it drips through.