Good Ole Dry Gas Cures My ill

Run as much of that old fuel out before re-fueling. What you have done is forced the water to be adsorbed into the gas. The engine runs mostly well.
With droplets of water coming up the line, engines don't run well. Keep running the tank as low as possible for a while to get rid of all suspended water.
Fuel treatments do not suspend water, just keep the fuel from separating, another no no.

Flounder, Flounder, Oh, I remember, You were going to ship me some fresh Flounder...

Yea,, Yea,, I remember well now.

Send pictures of happy people with the shipment.

Just what I said. Fuel stabilizers keep the ethanol and treated fuel from separating a lil longer. Eventually, it will. Chemistry says so. As you said, consume / burn it off. My outboard 20 does a lot of sitting. That fuel gets pumped into my van when it sits on the trailer within a month.
Think of oil and vinegar dressings; they will separate.
The dry gas CleanSlate makes reference to is is another old school de-natured alcohol.
It will absorb water and stay suspended in the gas a good bit longer. Still, it has to either get burned or poured out. Any alcohol or treatment will only hold so much water before it too, separates from the gas and sinks to the bottom with the already pre-separated junk, it's junk and a lot of water.

Ruel 1; Don't let any gas sit.
2; Only the best non-ethonol fuel.
3; Change filters often. LAST SUMMER??? Bad joke rite? Gonna have to take you out back with a switch...
4; Don't count on any filter or snake oil to substitute for the above rules.

If the water is absorbed in the alcohol, then that is suspended in the gas, I am not sure you would see the water in a bowl until it re-separated.

The bowl idea is great. Have the older style Racor gas filter with bowl on our outboard 20. Never found a drop.
But then, we do not store fuel and follow the above rules.

CleanSlate may have room under his OEM spin on filter to update it with a Racor spin on with a metal bowl.
Something in the back of my mind reminds me; inboard mounted filters for gas must be metal & not plastic.

For easy reading (Not ABYC or CFRs) I found these pages in the BoatUS site.

https://boatus.com/magazine/2014/june/installing-a-remote-fuel-filter.asp
Filters with a plastic sightbowl must be mounted outside of the engine space to meet ABYC standards.

Anyway to pump out remaining gas into your and girlfriends truck at the end of the season or before any long (4weeks) storage?
Run real low, carry more girlfriends in the back.
Here is where big fuel tanks come back and bite ya.
Does your gas station or marina sell ethanol free fuels?

I think you already have a spin on filter on the engine.
Find the correct Racor replacement with a metal bowl. **
Sadly, it is below deck and you can do a quick drain (not running) into a metal cup to check for water.

Your idea about a separate bilge space is a rule bender. I remember studying new builds vs CFRs. Usually below deck spaces share the same ventilation and drainage. Therefor, per the CFRs, mounting a plastic gas filter in the next compartment would not work. A good surveyor or forbid, an insurance investigator will look for these things.

On your ship, single SBC, one filter is all you need. There is a fine filter already in the Carb fuel inlet also.

Filter mic?
Oh heck, another headache.
Lets stay with what ever the factory rating is on the original OEM filter.
Efficiencies of the filter media is not going to stop water from passing thru.
NY123 I think mentioned this above and I have proven it my self. The best oiled filter media will still pass water.


Now, probably the easiest way to check your water and not mess with all of this;
Cycle thru your fuel. 100% fresh non ethanol fuel with no over the counter snake oils.
Spin off your filter and pour into bowl away from the boat.
Lots and lots of "open bonnet" ventilation before you try to start the engine after filter service.
Spin on a new filter.

The idea of spin off / on the same filter sux.
The O ring swells when it comes in contact with fuel. Putting a used O ring filter may never seal correctly.
Spin a new filter one on always.



**
Like these; https://www.westmarine.com/search?Ntt=Spin-On+Fuel+Filter/Water+Separator

That should be Flounder is in the mail,,,

Just remember to keep a check on your filters. Keep sets of spares in a dry place.
I and a friend keep our spare filters in the truck when we purchase in bulk, one spare on the boat.