Water in Fuel Tank--Again!

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
floater
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Water in Fuel Tank--Again!

Postby floater » Sat May 13, 2017 4:24 pm

Today I took out my 1988 Revenge 20 W-T for a test run. I put in 50-litres of fresh mid-grade gasoline, along with some SeaFoam and fuel stabilizer. The outboard engine ran well for about 10 minutes, then died--just like it did last year when I had a load of water in the tank.

I hooked up the spare [fuel] can I brought along, and the outboard engine fired right up. This leads me to believe I have water in my gasoline fuel tank--again.

Last year I removed the fuel tank, and had [a local company repair the fuel tank by] welding and coating [the fuel tank] with some poly-urea. The only [difficulty] I had was finding a gasket for the dual pick-up cover plate. The cost from [Florida Marine Tanks--a fabricator of fuel tanks--]was over CA-$200 for a 6-inch rubber gasket.

[Instead of getting the gasket from Florida Marine Tanks] I got some [gasoline-resistant] gasket making material, and--along with some gasoline-resistant caulking--I made and installed [my own gasket for the dual pick-up cover plate on the fuel tank].

The past few weeks [brought] rain. The top of the [gasoline fuel] tank and about a half-inch of the deck was awash in water. I drained all [the water on the deck] with a 12-Volt water pump. I figured all was good-to-go.

Now I am seeing this may not be the case.

It is back to removing the tank--again--and having it pressure-tested at the same place, to find out if they actually did [the work] said they would do, or if I made a [poor] gasket.

I will post [in the future with the outcome].

jimh
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Re: Water in Fuel Tank--Again!

Postby jimh » Sat May 13, 2017 4:42 pm

After you had the local welder repair the fuel tank and coat the fuel tank with some sort of material, and after you made your own gasket for the fuel pick-up cover plate, did you perform any sort of test of the repaired tank to see if it held pressure?

floater
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Re: Water in Fuel Tank--Again!

Postby floater » Sat May 13, 2017 5:43 pm

Nope. They told me they tested the tank prior to me making this gasket but I don't see how they could have. When I took it in there the woman running the place made all kinds of promises and failed to keep them all. I looked inside the tank when they were done and If there was any aluminum welding done on the outside it didn't show on the inside. I think they just painted this tank with their polyurea and said it was good to go. I'm going to take it back and have them test it with all the fittings attached and see what happens.

cc378
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Re: Water in Fuel Tank--Again!

Postby cc378 » Sat May 13, 2017 6:22 pm

The best thing I did for my 1990 Outrage 25 was replace the tank. A 1988 tank has had a good life... Why not have a reliable local firm make you a new one?

floater
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Re: Water in Fuel Tank--Again!

Postby floater » Sat May 13, 2017 6:34 pm

I asked two fabricators for a price and both were $2300. And to get a new FMT was US-$1500 shipped to the border. After tax and duty it was almost as much as the fabricator's tank. I'm back to red portable tanks [until] I get this figured out. They are okay to use. I only use about 13-liters with the big engine going out and back to the fishing grounds. The smaller 15-HP lasts about three days trolling back-and-forth.

floater
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Re: Water in Fuel Tank--Again!

Postby floater » Sun May 14, 2017 4:07 pm

I pulled the floor today. I removed the vent hose, from the fitting on the port side, and blew into it till it wouldn't take any more. I partially filled the cavity, added soap, and then covered the surface with soapy water as well. The only place I saw bubbles was right on top of the access hatch for the dual pick up. It was leaking air around two bolt heads but not allot. There were no bubbles coming from around the tank bottom or any of the hose fittings and fuel gauge. After removal of the pick up hatch I noticed some of the bolts had little plastic 'washers' around them and the two offending ones didn't. I guess I didn't notice they were missing last year. I'm back to square one now with a missing gasket though. I made the one last year out of a rubber paper sheet that was designed to be resistant to gas and oil. The gasket was in good shape but I'm going to replace it with a cork one anyways. Can anyone recommend a product I could use to 'paint' over the pick up hatch and the surrounding tank with? I just want something that will give me a little more protection against water intrusion after a heavy rain fall. I don't believe this could have lead to enough water intrusion to stall the motors. I left the tank 1/4 full all winter but I did add two full bottles of ethanol treatment. I'm not sure how else water could have gotten in there.

jimh
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Re: Water in Fuel Tank--Again!

Postby jimh » Sun May 14, 2017 5:16 pm

What border does the FMT tank have to cross?

floater
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Re: Water in Fuel Tank--Again!

Postby floater » Sun May 14, 2017 5:46 pm

[The border that the fuel tank manufactured in the USA has to cross is the] Canadian border.

I made some gaskets today out of the Felpro rubber cork sheet. Some funnels were the perfect size for cutting the sheet.

<a href="http://s123.photobucket.com/user/sterios/media/ring_zpskoi9euo4.png.html" target="_blank"><img src="http://i123.photobucket.com/albums/o316/sterios/ring_zpskoi9euo4.png" border="0" alt=" photo ring_zpskoi9euo4.png"/></a>

[YOU CANNOT POST HTML into the forum. That is why all the HTML tags above do not work. Go to the server that is hosting this image and copy the DIRECT url. Then use the IMG tags. See below. To understand how to do this, look at your post in the EDIT mode--jimh]

Image

This shot is of the dual pick up plate. The grey caulking was supposed to be fuel resistant but I guess it couldn't stand up to water evidenced by it's wrinkly appearance.

<a href="http://s123.photobucket.com/user/sterios/media/hatch_zpsfdlgnxu4.png.html" target="_blank"><img src="http://i123.photobucket.com/albums/o316/sterios/hatch_zpsfdlgnxu4.png" border="0" alt=" photo hatch_zpsfdlgnxu4.png"/></a>

[YOU CANNOT POST HTML into the forum. That is why all the HTML tags above do not work. Here is the image posted in-line in the thread:]

Image

I will not be re-using the two 3/4-inch filter screens at the end of the pick up tubes this time. I had to glue the screens back onto the plastic mounts last year and used some two-part marine epoxy. When I took out the pick-up, both screens had fallen off. I have a fuel water separator further down the path towards the motor and any debris should be stopped there.
When I put it all together tomorrow after screwing it down I'm going to use some 3M5200 on the screw heads and around the rim of the plate. After it cures I'm going to cover it all with butyl tape and a sheet of 6-mil poly-plastic to make it even more water proof. I hope to never have to get this cover off again.

jimh
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Re: Water in Fuel Tank--Again!

Postby jimh » Sun May 14, 2017 7:27 pm

I would have thought that the NAFTA agreement would have eliminated a CUSTOMS IMPORT DUTY on a fuel tank. What is the category of manufactured-in-USA product that would be used for importation of a fuel tank made in Florida into Canada? What is the duty? Does it vary by province in Canada?

floater
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Re: Water in Fuel Tank--Again!

Postby floater » Sun May 14, 2017 7:34 pm

You can substitute 'duty' for exchange rate! My mistake.

jimh
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Re: Water in Fuel Tank--Again!

Postby jimh » Sun May 14, 2017 7:37 pm

Your reply is not clear. Perhaps you meant to say you should have said "currency exchange" instead of importation "duty." If that guess is correct, then I think you are saying there was NO CUSTOM IMPORTATION DUTY on the importation of the fuel tank--right?

Wweez
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Re: Water in Fuel Tank--Again!

Postby Wweez » Sun May 14, 2017 8:05 pm

I am sorry, projects are difficult and then having to start over is harder. Sympathy and understanding! Good Luck.

jimh
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Re: Water in Fuel Tank--Again!

Postby jimh » Sun May 14, 2017 11:46 pm

Re the failure of the "glue" that was used to adhere the filter screen to the end of the fuel pick-up tube in the gasoline fuel tank: it is not surprising that the adhesive failed. Gasoline is a very good solvent, and by being immersed in gasoline for weeks and weeks, it would be a very unusual adhesive that could sustain its bond between materials as different as a plastic pick-up tube and a metal screen. In order to attach a metal screen to the end of a plastic fuel pick-up tube that is going to be immersed in gasoline--or perhaps even worse, in a mixture of ethanol and gasoline--some sort of mechanical fastening or bonding will probably be needed. Gasoline that has been mixed with ethanol has been shown to be a very aggressive solvent and can dissolve all sorts of resins used as adhesives.

floater
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Re: Water in Fuel Tank--Again!

Postby floater » Mon May 15, 2017 4:00 pm

I found some small plastic washers and "o" rings today at a Big Box Store. They were the perfect fit for my access plate.

http://i123.photobucket.com/albums/o316 ... ayeks8.jpg

I used both the 'o' ring and washer in the hopes that the washer would squish the 'o' ring enough to make a seal against the screw shaft.

After installing the access plate I further covered the edge where it meats the tank with some Butyl Tape. This stuff is water proof and shouldn't come in contact with the gas as the Cork gasket is there as well.

http://i123.photobucket.com/albums/o316 ... wktz8d.jpg

I blew air into the vent hose again and tied it off. After half an hour the tank still held air. I'm going to leave it open for now and test is with soapy water in the morning. If all looks good I will put the floor back on and fill her up and go for a boot in da boat!

quickenberger
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Re: Water in Fuel Tank--Again!

Postby quickenberger » Mon May 15, 2017 4:57 pm

There are a few sealants that are gasoline proof that you may consider if needed. One was commonly called B-Half in the aerospace industry. Its a polysulfide 2 part sealant that is aviation gas proof. We used it to seal integral fuel tanks in aircraft wings. Ethanol will reduce its life so if at all possible do not use ethanol gas. Here is a link to what can be used.
http://www.aircraftspruce.com/catalog/a ... ckkey=4275
They also have one that claims to be ethanol resistant, but I have never used it before.
http://www.aircraftspruce.com/catalog/a ... ckkey=4275

floater
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Re: Water in Fuel Tank--Again!

Postby floater » Mon May 15, 2017 5:14 pm

Thanks quickenberger. I have one of their catalogues and I totally forgot to check there!