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What do people feel is the most reliable fitting style for connecting to portable fuel tanks? I run two 6-gallon Moellers on my 15 and have OMC-style fittings, following the lead of the previous owner. They seem to have a good deal of slop even when new, and I have had air leak problems in the past. At this point I keep a spare on board but I'd prefer to not have to worry about it.

Looking at the marineengine.com site, I see Honda, OMC, Nissan/tohatsu, Suzuki, Mercury, and Yamaha. Any preference? Thanks.

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Everyone knows I am a Merc guy, so take that into consideration, but for my money the old style Mercury "bayonet" fittings are still the best you can use. They are little larger in size and price, but are absolutely leak proof and rock solid secure, and can be used with any engine brand at the tank. I am talking about the original aluminum fittings, not the cheaper plastic knockoffs. Avoid those.

You can see one here:

http://smg.photobucket.com/user/lgolt...4710541322

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Thanks Finnegan. They do look like they have the long shaft to ensure alignment. I assume the Mercury units are better than aftermarket? Would you have part numbers by any chance, or a pointer to an online vendor?

Tim

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2nd the mercury fittings.

i dont know what bayonet style is, but i (my brother) have a 2001 merc 40hp.

they are tough feeling, like if i dropped them they wouldnt break. they are so snug, and have never had an issue. nor with the originals on my usta-whaler powered by a 1996 merc 150 offshore.

original gas tank and original fuel line parts on that.

the fittings are solid, original.

i have some non oem johnson fittings, think they are moeller, and they feel like garbage, i can't comment on oem omc.

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After some additional looking around, I see original Mercury / Quicksilver parts available, and various aftermarket ones, including Moeller and Attwood. They all seem to be made of aluminum. Is it important to stay with the Mercury OEM, or are the aftermarket ones OK too? The latter seem more widely available, so I am thinking about the Attwood ones.

Tim

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Tim -

After suffering from Tempo/Moeller quality issues, I skipped aftermarket and went OEM.

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Since Attwood is a Brunswick/Mercury owned company, I would not hesitate to buy the Attwood Mercury bayonet style fittings. The female fitting installs on the tanks, and the "bayonet" fitting on the fuel hose connects by quickly pushing in, followed by a 1/8 right twist.

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Thanks Finnegan, exactly the info I needed. For some reason I can only find the Merc OEM in 3-packs at $100 a pop. No thanks!

I appreciate the assistance.

Tim

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I inherited a 12 gallon steel tempo long cruise tank that had the Merc bayonet fittings attached. I have used it for three seasons now and I am very satisfied with the durability. Finnegan is correct; best fittings out there, even if they are 46 year-old technology (or more). The older (made in the USA) the better. And it feeds a 1997 Evinrude 90SPL crossflow. I do not care about cross brand fittings; I only care that I have reliable hardware.

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I agree with Finnegan. I used the metal bayonet Merc fittings in my 90 hp Yamaha powered Montauk for about 20 years. Never had a problem.

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So I acquired the Mercury fittings, and am sorting out the final pieces. One concern is that the long body on the Mercury fitting will put stress on the tank fitting, through simple leverage. The Moeller tanks I have use a nylon-filled plastic piece that the female fitting would screw into - that is a concern given that the fittings when clipped together form a lever around 6 inches long. I'd be concerned if it was metal, too, but with plastic I don't think I want to risk it.

So I am thinking of installing a short piece of fuel line between the female fitting and the tank - maybe 6 or 8 inches. As much as I hate making extra connections, which could leak, that will prevent putting any torque on the tank fitting.

Reasonable?

Tim

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Tim - Don't worry about it. I use the Merc fittings on a pair of red plastic Tempo 12's, Montauk style, on my Ribside 21 when I need extra fuel capacity, and the Tempo/Moeller withdrawl fittings hold the Merc connectors well, with no problems. The plastic tank fittings are actually quite strong and have that large hexagonal nut support fitting on the top. and are designed to rotate 360 degrees.

When you plug in the fuel line, one hand holds the receptor fitting, while you push in and twist the insert fitting. There is really no stress on the fuel tank plastic fitting itself.

Give it a try, you'll see that it works fine.

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Finnegan, thanks for the data point. I do have that Moeller fitting that can rotate 360 degress, so sounds like the same setup as yours. I was concerned about pulling on the hose or banging the fitting, but I will follow your lead. Now I just need to find out what fittings thread into the tanks and the Merc female fitting - it came with a hose barb, which is obviously not going to get it done.

Tim

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Tim, when you find the right part numbers please let us know. I have the 12 gallon Moeller tank as well. Currently just connecting the fuel line direct to the fuel filter on the engine and plugging the hose when not in use (99.9% of the time). I too would like to incorporate the old mercury fittings. At least until I start using the onboard tank but that likely will not happen until 2015. The merc fittings should be enough to supply fuel to a thirsty 225 hp Yamaha 2 stroke right?

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I believe the fittings are 1/4" NPT

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The male fitting is 30185T 3. It comes with a 5/16 hose barb installed.

The female fitting is 22831T 3. It comes with a 5/16 hose barb, not installed.

My Moeller tank takes a 1/4 NPT fitting. The female Mercury fitting takes something smaller - maybe 1/8 NPT?

Will take a trip to the store to find out.

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Almost all of the Mercury female tank fittings come with both a barb fitting (for use when it plugs directly into the connector on the engine) and a 90 degree elbow fitting, for use on the tank. I believe most are now 1/4" - 1/8" NPT.

They all seem to use the 90 degree fittings.

http://www.iboats.com/1-4-NPT-Aluminu..._id.215275

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Thanks. I'm guessing it is 1/8 NPT on the connector end - appears so in this Moeller version: http://www.amazon.com/Moeller-Marine-Connector-Mercury-Bayonet/dp/B000MTB7KQ/ref=sr_1_20?ie=UTF8&qid=1406634193&sr=8-20&keywords=mercury+fuel+line+fittings

Attwood also seems to make this connector out of nylon: http://www.amazon.com/Attwood-Mercury-Mariner-Fitting-4-Inch/dp/B000FJS85A/ref=sr_1_fkmr1_2?ie=UTF8&qid=1406634441&sr=8-2-fkmr1&keywords=mercury+attwood+fuel+line+fittings but I would prefer to stay with the aluminum.

I will get a 1/4 to 1/8 NPT nipple and see how I make out.

Tim