How to run two outboards off one tank?

[Fishing Junky]

Howdy Guys. Can anyone steer me in the right directions on making up a gas line that I can run a 25 Honda and a 8hp Yamaha both fourstrokes on one gas tank? What parts would I need and where to get 'em? Any pictures of a hose on the net I could look at? Any help would be greatly appreciated. Thank you. Junky..

[Capt. Don*]

Ok, I run two outboards on my boat and have 2 150 gal tanks, with the manifold system from the factory I can run either engine from either tank or both in any combination I choose. The system is simple, you need to install a 3-way valve from your tank and connect both lines to it. You now can select which engine will get fuel. It you don't want a selector valve you can install a tee at the tank pickup and attach each fuel line to one leg of the tee. As long as the connections on each end are air tight the engine that is running will get the fuel, or both engines running at the same time for that matter.

Tempo products supplies most of the fuel fittings to the marine manufacturers, look here...[Note from admin: Please read forum policy before posting again. Thank you.]

[Fishing Junky]

Thanks for heading me in the right direction CD. Appreciate it. Junky......

[Valv]

Actually you cannot have a Tee to feed both tanks.

You need a 3 way valve, otherwise the motors will always try to suck from each other and get air in the system.

[Fishing Junky]

Valve. Wouldn't the valve in the bulb in the motor that wasn't being used prevent that? If not, what would be the fix on this setup, besides the 3way valve? Thanks for the help.

[Valv]

Fishing+Junkie, the bulb on motor is not enough to stop air flow from motor.

Somebody brough up this question some time ago, and also was the cause of a malfunction for some members with that setup.

You need a valve that stops completely the flow from the "unused" motor. You can try to see if it will work with your setup, it migh be possible, then if it doesn't work you'll need a valve.

[Capt. Don*]

Lets think about this. With a tee and check valves in the primer bulbs, the running engine will draw fuel from the tank and through the tee, in order to overcome the check valve in the primer bulb, the supply from the tank would have to have a restriction equal to or greater than the vacuum needed to break the seal on the check valve or the clamps on the barbed ends of the fuel line connections and draw air in. This doesn't seem very likley to me. I think it is worth a try.

[Valv]

Don, you can try all the theory of this world, there are members here that went thorugh this same issue and only way out was to get a valve. I've never done it before so I cannot guarantee that's what's needed in this case, but since he has to cut fuel line anyway as might as well try just a Tee, if it doesn't work there is always plan B (the valve).

Also if he has a portable tank he can switch between motors with no problem, he could buy 2 quick connectors to the tank and swtich between motors.

[Fishing Junky]

Fight nice boys. Just kiddin'. I see both of your points. I guess I should just go with the 3 way valve. Hoping to just plug in the lines to the motors and call it good, but if the tee doesn't work, then I just wasted money on the tee. The valve would require one more move, select what line to draw, but that's not so bad. Thanks for your insight both of you. I thought I read a topic on this subject, but went all the way back into the May threads and didn't find anything. Also a search was no luck to me. Thanks for the links to valves and connections also. I searched the net and had no luck, so again, thanks. Junky...

[marine_man]

You'll either need a three way selection valve (where you select which line gets the fuel) or connect directly to a fuel tank pickup (I've heard of some guys bypassing their reserve valve on the Lund Pro V's, Tyees, etc) and connecting the lower pickup to the kicker motor)

Valv is right...

marine_man

[Capt. Don*]

Now I am curious, not only if the tee would work or not, but if not why? As I stated earlier, I run two outboards, 225hp which draw a much higher volume of fuel than FJ's. I have two 3 way valves, one for each tank, if I choose to run the both engines off of the port tank, for instance, ( which I've done numerous times for many miles), I have nothing more than a tee feeding both engines. I ran 145 miles today w/twin diesels drawing off of a single tank with not two pickups, but, you guessed it, a tee. I don't know how Lund tanks are configured when it comes to reserve and main pickup, but I would guess that the reserve pickup just drops lower into the tank, much like bigger boat tanks which have shorter fuel pickups for generators and deeper pickups for propulsion engines. I am certainly not trying to fight as FJ kidded, but I want to know why something I do regularly isn't supposed to work? Have I really been just this lucky, if so, whats the powerball jackpot worth now?

[Fishing Junky]

CD, I should have told you guys that I have a portable 6 gallon tank in my boat. 2006 Lund 1625 classic. It is my BWCA boat. I don't have room to run even a seperate 3 gallon tank for the kicker. I want to run both motors, which are very fuel efficient, off my one portable tank. I could do what Valv said and just switch gas lines, but would rather have it so I can run either motor without the hassle and slight gas leak changing lines. I hope I'm not making a mountain out of a mole hill here. Just trin' to get some ideas. And I thank you very much for your input as well as Valv's and others. Junky.....

[Surface Tension]

As with most things there more then one way to do something. A check valves intended purpose is to keep gas from flowing in one direction as you prime the line and fill the carb.

You can use a T but your relying on both check valves to be operating at 100%. So as long as the check valves in the primer bulbs are good then you won't have a problem. Thing is these valves don't last all that long and eventually will let some gas go by. Used on a single line its not a problem and you won't notice a leaking valve till it shot completely. Hook up a T and you will start back drawing gas through a check valve thats not 100%.

Another way to do this which is also intended and recommended for this application is the 3-way valve. Now your not relying on check valves.

[Valv]

Ok, Ok, I did a little research and found some of the articles:

http://www.fishingminnesota.com/forum/showflat.php?Cat=&Number=114214&page=&view=&sb=5&o=&fpart=1&vc=1

http://www.fishingminnesota.com/forum/showflat.php?Cat=&Board=UBB9&Number=125904&Forum=

http://www.fishingminnesota.com/forum/showflat.php?Cat=&Board=UBB9&Number=632889&Forum=

[Fishing Junky]

Wow Valv, ya didn't have to go through the trouble of finding those links, but I do appreciate it. I read through all of them and great info. I'll just go with a three way and be done with it. I really appreciate everyone's help. Good stuff. Junky.....

[Bigeye30"]

Wow thats interesting never knew that could be a problem but I will say that I currently just use the T system on a 100 Horse Yamaha 4 stroke and T off to a 8 Horse Yamaha 4 Stroke Never had a problem for the past three years but do know now if that ever becomes an issue whats probably causing it, I switch between the two motors quite often and even have the 8 horse disconnected through out the year but like I said Ive personally never had an issue with it.Thats just my experience

[Valv]

FJ it wasn't troubles, being on this forum for many years I remembered the issue and did a quick search.

As I said I cannot tell you how to do it since I never installed anything like that, let us know how it turns out.

[Fishing Junky]

Won't be till next spring Valv, but will come back and tell everyone how it went. Thanks again, and to all. Junky....

[kjgmh]

Another good option is to mount a fuel filter/water seperator. You can run 1 or 2 inlets and 1 or 2 outlets with no problems. This will also prevent any debris or water from gettting to your motors. Yamaha has a nice little one that would work great in your application.

[kjgmh]

Capt Don, one thing to consider is that the motors FJ is dealing with are both carbed. This makes it much easier to suck air from the other motor. On your diesels it is a sealed fuel system and much harder or maybe impossible for this to happen. Not sure on your 225's but on most of the newer ones they use a vapor seporator tank which also makes this harder to happen. If you are running both motors at the same time, which it sounds like you are doing, this also is not an isssue.

[Capt. Don*]

Hello, the points you raise are well taken, however, the primary point I contest here is that the fuel needed will be supplied from the tee. Air has nothing to do with it unless there is something else wrong. In order for one engine to starve for fuel the supply would have to restricted enough for it to try and draw fuel from another source, the old path of least resistance if you will. That means overcoming check valves, hose clamps, needle and seat in the float bowl etc. In a situation where everything is good, this won't happen because the path of least resistance is from the tank through a tee and into the engine. Have you ever had a vapor separator tank on a newer outboard apart, I have, you know whats in there, a float, a needle and seat and the pickup for the electric fuel pump, just like a carb bowl. The fuel supply pump is still the same old crankcase pulse style diaphram pump that was used on the ol' 1970 Johnson Sea-Horse. I guess some things don't need to change. I have been astounded by the number of posts provided by Valv of people who use this system and claim no problem, yet are convinced that there must be something to it because they heard about someones cousin had a friend whose mother had a grandson who... you get the picture. And to think that if everything was fine for 3 years of operation and a problem developed there would be a need to add a part that wasn't there before to solve it? I don't understand the thinking, I posted this info for FJ because it works and via other posts it has worked for them, not to try and debate with people who provide no basis in fact. I have experience with it, I understand it, and it works. As far as diesel fuel systems and air....I don't even want to go there.:)

[TSCTSC]

Fishing Junky,

I was the poster in one of the links that Valv put up. I have come quite a long ways since I posted those questions. Boy, was I green, and boy, did I get such great help from this site. Thanks again to all those that helped me along. Was like going down memory lane reading that old post. Hehe. Thanks Valv.

In any case, I chose not to go with a T valve. The T-valve is the least that you should go with if u do not want to potentially screw your motors. I assume that they are both 4 strokes.

Currently, my fuel set up is from my internal fuel tank to a fuel water separator. This allows a 1 in and 2 out fuel line. All my motors are Yammy but for some reason, the dealer who is Yammy installed a merc fuel water separator for me.

The way I see it, it serves two great function. It streamlines my fuel delivery, and it also filters my gas. Perfect. Have been running it like this for 6 months with no problems at all. That was why I went with the fuel separator route. If u buy the motor from the dealer, get them to install all of it for you. It should be free then. Also, mount the separator outside in the splashwell so that u can access it easily. Mine is on the port side of the splashwell at the back of the boat.

[Valv]

Don , the point is why take a chance when you don't have to. I guess this will be a factor of decision when hiring somebody to take you out on a large body of water.

I am NO expert, I just use common sense, and it got me many places, the basics of this debate is common sense, if you decide not to see the other face of the coin, that's great, I have no problem with it but don't give any suggestion based on your "theory".

When I write on a thread I know what I am talking about or I don't even bother writing , I am always responsible for what it could happen to somebody when replying, and/or if I don't know much about an issue I warn people about it.

The Internet is a very powerful media, you will be surprised how many people read every thread and take conclusions, it's not just a couple of guys debating. If you are comfortable assuring somebody that your idea is the actual fact, that's fine for me too, but I would at least offer to come at rescue if it doesn't work, right ?

OK, now the issue has been partially resolved, pending a reply from F.J after he tries the suggestions (lots of pressure on you Fishing_Junky :grin )

Let's put down the war axe and go get some fishing done, that's what this Forum is all about

[Capt. Don*]

Valv, you are absolutely right, chances should not be taken when not needed. Frankly it doesn't matter to me which method is used as long as it works and is a simple install.

On another point, are you insinuating that I take chances with my boats or passengers based on the information in this thread? I certainly hope that is not the case. My boats have traveled over 15,000 miles and carried over 6000 passengers this season with out a single mechanical failure or incident, I feel this record speaks for itself. I am no expert myself, but experience and knowledge have served me well. I am a maritime professional and have the documents and service records to prove it. I would like to invite you to fish with me next season, you'll gain a whole different perspective.

Thanks

[Fishing Junky]

Hey Guys. I have all the neccasary hardware to build my fuel line. My next question is: Can I use regular teflon tape on the brass threads were I need to hook up to my 3-way valve? If not, what should I use? Thanks again for the help. Junky....

[John Mickish]

Do not use teflon tape on any fuel lines. There is a chance that some of it could come off durring the instalation process and that would be very "ungood" to any carburator/injector that it lands in.

[Capt. Don*]

I have installed several Floscan units to marine fuel systems, this involves plumbing sensors into fuel lines. I have used a product called Loctite PST 565, it is designed for sealing fuel fittings and I have never experienced a leak with it. You should be able to get it at any auto parts store, if not in stock they could order you a small tube. When you apply it be careful not to get it inside of the fittings, only on the outside of the threads. Good luck!

[Fishing Junky]

Loctite it is. Thank you very much for the advice. Appreciate it. Junky....

[Fishing Junky]

Unfortunatly, this motor will be put in the for sale section as soon as I get the ok to post. I paid for the ad, so keep an eye out in the for sale if interested. Junky...