# Run main and kicker off same fuel source?



## SwollenGoat (Apr 13, 2005)

This may seem absurdly simple to some - just bear with me.

My 17' Fisher Deep-V has a 30 gallon internal tank which runs my 90hp Merc. oil-injected 2-stroke. I always carried along a 6 gallon tank with mixed fuel for my 2-stroke kicker - it was not injected. I just replaced the 2-stroke with a Merc. 4-stroke 9.9. 

Should I run both the 90hp and the 9.9 off of the same internal tank?
(Would love to not have to trip over that gas tank anymore.)

If so, do I...

1. Manually switch the 1 fuel line between the motors as needed?

2. Split the fuel line with some kind of "Y" fitting? If yes, do I need a primer bulb on each end? Also, is there any harm in running a 2-stroke and a 4-stroke off the same fuel source? I have an in-line glass fuel filter on the fuel line and I have seen the 2-stroke oil tends to "back-feed" a little bit into the filter.

Again, sorry if this sounds silly - just never done it before.


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## Hetfieldinn (May 17, 2004)

No problems doing so. Install a 'T' fitting on the main line. From the 'T' fitting, you will need a length of fuel line, with a primer bulb on each, to go to each motor.

As long as your two stroker is oil injected, there won't be a problem.

I run my Optimax 2 stroker and my 4 stroke Pro Kicker off the same tank.


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## SwollenGoat (Apr 13, 2005)

Thanks Het I figured you Erie guys would know. 

BTW - do you ever worry about something going wrong with only 1 tank? (Fuel contamination, bad gas etc.) Do you usually carry a spare tank for an emergency?


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## Hetfieldinn (May 17, 2004)

I've never really given it a second thought. My tank is plastic, so I know there is not and never will be any rust in it. I rarely, if ever let it go to less than half a tank. I always run Sunoco, Shell, or Mobil gas. And I add a can of Sea Foam at least every third tank of gas.

I never carry a spare tank. I usually know someone else out on the water, so If I needed a tow back in, I would think it would't be a problem.

The thought of failure to be able to get back to the dock has never entered my mind. If it got me out there, it should most likely get me back.


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## cw261 (May 11, 2004)

I did the same thing - I added a shutoff valve right off the tee going to the kicker, and shut it off when not using the kicker, but it's probably not necessary. Frees up some extra room in the back of the boat!


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## Toolman (Jun 8, 2004)

SG,

If your boat is newer than say, a 2000 year model, it may have 2 pickups on the gas tank. If you can't plumb it directly from the main tank then (from what I understand) you definitly want to add a shut-off valve to keep from siphoning gas out of the 2 stroker while you are running the kicker. 

Tim


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## SwollenGoat (Apr 13, 2005)

Thanks for all the replies. My boat is actually a 1997, I will check to see if by chance it's plumbed for two lines. I believe my fuel tank is aluminum. The shutoff valve sounds like a good idea. I'll try to post back with more info. as I progress.


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## Toxic (May 13, 2006)

On my 97 Trophy I run my 05 Yamaha 150 2 stroke and & 9.9' 4 stroke the same way as Het's with no problems. I have two primers and only one sending unit, and no shutoff valve.


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## Toolman (Jun 8, 2004)

Not thta it can't be done, but there can be implications from a simple "T" fitting even with seperate primer bulbs. Here's a couple of threads from WC that address this:

http://www.walleyecentral.com/dc/dc..._id=260144&mesg_id=260144&listing_type=search

http://www.walleyecentral.com/dc/dc..._id=258070&mesg_id=258070&listing_type=search

http://www.walleyecentral.com/dc/dc..._id=233635&mesg_id=233635&listing_type=search

Tim


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## JIG (Nov 2, 2004)

Worked with one bulb for me. As long as the lines stay hard itll run both. Its just priming the pump. Worth puttin a in-line filter also. Good to have both motors run at the same time. If the 9.9 isnt enough just fire the other up and straighten out. Wouldnt want to troll in windy conditions without my bigger motor ready too go.


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## SwollenGoat (Apr 13, 2005)

Just checked back and I think Toolman has come up with some very good info. There is a potential risk involved with running just a T fitting in that one of the motors could suck air from the other line creating a lean condition that could ruin your motor. I guess the "best" way is to install a water separator and run both lines off of that.

http://www.walleyecentral.com/photopost/showphoto.php?photo=3827&cat=500&ppuser=114041&sl=h

Thanks for the heads up Toolman.


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## lumpyman (Sep 11, 2007)

on my boat which was done by a marina the line runs to the fuel separater then to both lines from there there is a brass shutoff valve in the line that runs to my kicker. i don't use it the primer ball is all my honda needs the fuel separater takes care of any vacuum issues between motors. i do unhook my quick connect on honda before firing up merc. have had vacuum problems if i don't .the fuel separater is a good idea though mine is full of water every year when i change it.


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