Removing water from gas tank

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bcassedy
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Removing water from gas tank

Post by bcassedy »

Folks,

With the warm winter we had in the Cincy area, I worked on the boat a bit. One thing I did was to fill the gas tanks and add Sea Foam to prevent the gas from becoming unusable (something I've done for several years). NOTE - I also treated to gas that was in the tanks at the end of the season with Sea Foam to stabilize the gas for this year's usage.

As I'd had both knees replaced in late '16, my mobility wasn't where it needed to be so I enlisted the help of one of my sons. Unfortunately the gas cap on one side was left off after treating with Sea Foam and then topping off the tanks (guarantees a good mix). We've had rain over the last 6 - 8 weeks so my concern is the possibility of water getting into the tank. I don't shrink wrap (just cover the cockpit with a tarp), so any rain would've run down the gangway and possibly gotten into the tank as it splashed up against the fill fitting.

I'm looking for suggestions on how to handle this....

Some of my thoughts...
1. Disconnect the fuel line at the input side of the cartridge fuel/water separator, connect a manual pump ( https://shop.advanceautoparts.com/p/per ... fragment-4 ) and see what I pull from the tank into a glass jug.
--> If water present, pump until no water shows up (as pickup tube ends w/n 1" of bottom this should remove a significant amount of water.

2. Treat tank with Sea Foam or ??? to remove the remaining water.

3. Take the above mentioned pump and snake the intake into the fill tube (with a weight attached to ensure hose rests at bottom of tank) and see what I can pump out....
--> crud / water - keep at it until get no crud/no water.

4. Pull the sender unit out, drop the weighted hose to the bottom of the tank, and pump out in that manner.

5. Listen to what someone else has done. :-)

I'm not worried about what's in the gas lines att as they contain the treated gas from last fall. However, with the open fill fitting and the rain that MAY have gotten into the tank, I'm a little concerned about firing up the engine, even with the standard new fuel/water separator that'll be in place. Comments / suggestions?

Bill
Bill & Sharon Cassedy
"Sunset Seeker"
'88 32' Sedan Bridge to be sold (updtd 1-1-22)
"Sunset Seeker Too" (SS2)
'88 41' Marquis hardtop. (as of 1/1/22)
Located in Aurora, In.
Always fresh water.
honestcharlie56
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Re: Removing water from gas tank

Post by honestcharlie56 »

On my boat (see the sunken 32' thread). I pulled the lines off the inlet sides of the fuel pumps and pumped out a few gallons from each tank. Stopping periodically to fill a clear container so I could see what was coming out. Does your boat have a fuel manifold? On mine I am able to feed both engines from both tanks, each engine with its associated tank or both engines from one single tank. The right thing to do would be completely drain that tank. That being said I would drain some from the tank in question and make sure I was getting clean fuel. Throw some HEET in that tank and go. Are you in a place where you can run the boat in no currents. I'm in the gulf and a lake called Big Lake. So loosing an engine temporarily is an option for me. Might not be if you are in a high current river.
1990 Marinette 32 Sedan Flybridge "Hubba" Lake Charles, LA
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railrunner04
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Re: Removing water from gas tank

Post by railrunner04 »

:shock: sounds like a horrendous situation you have on hand there that looks like what you have planned will work the only x factor is the sea foam I seem to remember reading theres some kind of chemical reaction/bond with water in the fuel i could be wrong hopefully i am. Just to be on the safe side id pump out at least half a tank maybe more if there is evidence of fuel coming out of the vent tube! good luck!
Moby Rick
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1971
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TinLizzy
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Re: Removing water from gas tank

Post by TinLizzy »

Sea foam does nothing for water in fuel. Use heet or some other kind of isopropyl additive after you pump the tank dry. If you don't pump it completely dry, I believe that you will be fighting this problem for a long time. I have pumped out many boat tanks in my time. Usually put a primer bulb on fuel line and run hose out of the hull drain. Let gravity do the work. I use white 5 gallon pails and fill them a little over 3/4 full and the let them sit for a few minutes to let the water separate to the bottom. Then I dump the good gas into 5 gallon fuel containers, watching to see that no water is getting in the containers, and fill up everything with a gas tank I own besides the boat. Car, truck, lawnmower, etc. Then put a hot dose of heet in boat fuel tank and about 10 gallons of fuel. Run engines til almost out of gas, shut them down, pull fuel filter elements to check for water. If no water in fuel filters, your good to go. If there is water present, repeat process.
Rodney
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jralbert
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Re: Removing water from gas tank

Post by jralbert »

Agree - forget about the Sea Foam binding water or making it usable. Your plan and the others that involve pumping out and checking are on track, especially with the weighted line you propose. Assume you have a water separator in the system (The old Perkos with ceramic cartridges were great) which will take care of most of the water if not all. Empty it frequently.

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carl
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Re: Removing water from gas tank

Post by carl »

BigM
Last edited by carl on Wed Jul 10, 2019 12:05 pm, edited 1 time in total.
Fastjeff
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Re: Removing water from gas tank

Post by Fastjeff »

I'd close loop pump it out (and did on mine). I hooked a hose to the Perko separator, ran it to a high performance electric fuel pump, then to a cartridge filter with a clear plastic bowl beneath it. From there a hose went right back into the same tank.

Let it run for at least half a day and keep checking that clear plastic bowl for water and junk. The Perko (if you have one) should be drained every hour or so as needed.

Jeff

PS: Terribly sorry to hear about that open filler cap, and your knees.
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
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bcassedy
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Re: Removing water from gas tank

Post by bcassedy »

Thanks Jeff. Family's been calling me "bionic man" for some time. Left hip's gonna be replaced this September. Your idea is sound. I've got a 45watt solar collector charging all (4) the batteries. With the boat on the hard, there's really no draw on them. So having a 12v electric fuel pump recirculating stuff from the gas tank thru Perko and fuel filter should work well.

Thanks to all who have offered advice. I think I have a good handle on how to proceed. I may use different aspects of advice offered to ensure I get the water out PLUS cleaning out the tank.

Bill
Bill & Sharon Cassedy
"Sunset Seeker"
'88 32' Sedan Bridge to be sold (updtd 1-1-22)
"Sunset Seeker Too" (SS2)
'88 41' Marquis hardtop. (as of 1/1/22)
Located in Aurora, In.
Always fresh water.
DougDoty
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Re: Removing water from gas tank

Post by DougDoty »

The only thing I would add is if you can give the boat a lean in your favorable direction it will be easier to get the separated water corralled into the corner you have best access. I would also be considering a couple of inches of copper tube attached to the end of a semi flexible plastic line that was steerable to that corner. You can steer by sound and feel with the copper dragging on the inner wall of the tank.
1984 39 Marinette Sedan, " LIBERTY ONE " Warsaw KY, 440 chryslers, Westerbeke 9.0 kw , 1 3/8" shafts 93 1/4" long and 19x22 dyna quads or, 19x20 DQX's 38.5 MPH GPS best.
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