Should I install a Water Separator?

kaydano

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I will be winterizing my new 115 HP Mercury 4-stroke this week. Should I install a water separator? I'm getting mixed signals online...

Yamaha seems to recommend them, while Mercury seems to be the opposite.

It seems like a good idea, and it seems to be very cheap insurance (that's how I see it at the moment anyway), but there must be a downside or Mercury would include them on their motors from the factory.

Any thoughts/comments?
 
I don't see any downside when it comes to protecting your engine from unwanted water and other contaminents. I think any fuel system should have a good filter/water seperator, it's just insurance against bad things entering your $10k motor.
 
Like my Uncle used to say; "It couldn't hoight."
 
Yamahas come with one and Yamaha still recommends adding the extra filter, according to a friend who owns a marina.
 
I would add one. With the E15 gas on the horizon, you'll only need it more.
 
I installed this: My link

It took some convincing before my dealer would OK the installation (by me.) He said Merc told him I needed to remove the low pressure filter under the cowl. I did and it's all good. As mentioned previously, it's not the E10 I'm worried about, it's the E15.
 
All outboards need one. Wouldn't leave the dock without one.

Single, twin, or triple motors can use the fuel / water seperators.

Cheap Insurance

Todd
 
Okay, so based on all your comments, I decided to get one. I called the place that was going to winterize my motor, and the girl at the service desk said a water separator, installed, would be $25. I couldn't believe it was that cheap, but she insisted. I asked her if it was installed on the boat somewhere or inside the motor cowling, and she said inside the motor. The ones I saw online looked like the size of a regular oil filter, and there's no way something that big would fit inside my motor compartment, but I figured they must have some smaller version that would fit inside... Silly me...

So get this - When I dropped the boat off to get it winterized, I saw my order sheet, and she had written "replace fuel filter" on it! I asked another guy working there about it and he said a water separator would be $250-$300 installed, and it doesn't go inside the motor cowling. THAT price made a lot more sense to me, but I was disappointed. Anyway, I want to figure out exactly where I want to put it first, so I passed on it for now. I'll do it myself over the winter...

So, if there are any tips on where to place it, how to install it, and what brand/size to get, I'm all ears. Any problem putting it near the battery? Fuel and sparks obviously don't mix, but the thing would have to leak fuel AND I'd have to have a loose wire to get a spark, and BOTH would have to happen at the same time to set my boat ablaze... But I definitely do not want to set my boat ablaze.
 
Hey Kaydano, if you'll look in the photo gallery, page 2, patiently waiting, there is a picture of my dual battery setup. You can see the pre-rig Yamaha filter behind the fuel fill hoses. It's not a great picture, but it would give you an idea of where the factory puts it. If i get the chance this weekend, i'll take a better shot of it. Hope this helps some!
 
Now that you point it out, I can see it. How is that connected to the boat? To a hanging bracket or something? I sure they didn't put the bolts through your fence panel... Is it mounted to a rail? The other problem I have is my fuel line does not come up into the changing station compartment. Looks like they added a second hole in your floor. I have only one, and I think it's pretty full. I might be able to squeeze a splice through there...
 
I put my Racor in the motor well, forward of the motor. I drilled 2 holes in the aluminum rail that surrounds the boat. The fuel line comes down from the tank just ahead of the well and runs thru a grommet in the motor. It is easy to splice the Racor in right there. No additional fuel line is needed for this install. It is similar to the Yam installations I've seen. I'd get a pic, but the boat's in winter storage and a pic can't happen.

The smartest woman about Bennies is Susan here on this board. Not to sound sexist, but I'd trust no other woman's guidance than Susan's. Ask for someone else at the dealer. Nothing like a "know-it-all" of any gender.

Now that you point it out, I can see it. How is that connected to the boat? To a hanging bracket or something? I sure they didn't put the bolts through your fence panel... Is it mounted to a rail? The other problem I have is my fuel line does not come up into the changing station compartment. Looks like they added a second hole in your floor. I have only one, and I think it's pretty full. I might be able to squeeze a splice through there...
 
Similar to this example.
v680b9.jpg


I put my Racor in the motor well, forward of the motor. I drilled 2 holes in the aluminum rail that surrounds the boat. The fuel line comes down from the tank just ahead of the well and runs thru a grommet in the motor. It is easy to splice the Racor in right there. No additional fuel line is needed for this install. It is similar to the Yam installations I've seen. I'd get a pic, but the boat's in winter storage and a pic can't happen.

The smartest woman about Bennies is Susan here on this board. Not to sound sexist, but I'd trust no other woman's guidance than Susan's. Ask for someone else at the dealer. Nothing like a "know-it-all" of any gender.
 
I'm thinking about putting the water separator in the engine pod. The fuel line is right there, it's unused space, and if it leaked, gas would not get on the deck of the boat. The bad part is it's a tight space and most of the metal parts in the area are angled, plus the gas tank is sitting right there too (and is somewhat in the way). I'm thinking the best place to mount the bracket is bolted to the rub rail where the red oval is in the photo. The bracket (simply a small rectangle piece of aluminum) would be just tall enough to give just enough clearance to remove the filter as needed (the fuel tank is very close below).

Anyone see a problem doing this at this location of the boat? Anyone seen one put there before?

Dano
 
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Goldenrod - Thanks for posting that pic. It made me think about putting it in the motor pod. I don't know if I'll put it there for sure yet though. I'm thinking it will look a little stupid mounted in the pod where it will be in plain sight, but it seems like a practical location (gas lines are right there) and I won't have to cut holes in the deck to route gas lines into the battery compartment. If I can figure out a way to make it look clean and tidy (so it looks like it's supposed to be there) I'll probably put it there.

I also read online that Coast Guard requirements dictate the water separator be mounted "below deck" for outboards, and "above deck" for I/Os and inboards. I'm not sure if that applies to pontoons or not, but that's what I read. I also read extra long barbs should be used so two hose clamps can be used on each hose/barb connection. Thread compound compatible with fuel and ethanol is a good idea (I don't use ethanol, but its a good idea just in case). Just some info for anyone else reading this and considering doing the same thing.
 
That's where I did mine, although my pod is bit different from yours since my fuel tank is above on the deck.

Do be sure that there's enough room for your motor to tilt fully up and that you cut your fuel lines to insure a full range of turning motion.

Merc factory guys told my dealer I needed to bypass the low pressure filter on the motor. Easy to do with a few barbed fittings and clamps.

Also, double clamp your fittings.

I'm thinking about putting the water separator in the engine pod. The fuel line is right there, it's unused space, and if it leaked, gas would not get on the deck of the boat. The bad part is it's a tight space and most of the metal parts in the area are angled, plus the gas tank is sitting right there too (and is somewhat in the way). I'm thinking the best place to mount the bracket is bolted to the rub rail where the red oval is in the photo. The bracket (simply a small rectangle piece of aluminum) would be just tall enough to give just enough clearance to remove the filter as needed (the fuel tank is very close below).

Anyone see a problem doing this at this location of the boat? Anyone seen one put there before?

Dano
 
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Good point on leaving room for the motor to tilt. I hadn't thought of that.
 
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