Fuel Problems

Hi Guy's
Can anyone tell me the best way to keep the water out of my gas tank. I realize that it is the ethonal but I have a water seperator with a drain on it along with adding the Marine Sta-Bil and still have problem's.Thank's to anyone in advance.

Re: Fuel Problems

onboard or portable tank?

Re: Fuel Problems

What sort of "problems" are you having? The water seperator should take care of the water in the fuel. I run ethonal also but don't have water issues.

Re: Fuel Problems

Sorry it has a inbord 30 gallon tank

Re: Fuel Problems

Thanks for responding , the problem I have is probly 2 so long story short is I have a Merc 115 tower of power and if it sits out behind my house to long water forms in the gas and when I get on the water it get sucked into my seperator and fills it then the motor will die at anything over idle. When I drain the tank and put clean gas back in it runs like it should all the way throug the RPM's, this happened a couple of times then I switched to porable tanks but that did not last long because of the milage and range so I went back to the inboard tank and added the marine sta-bil. After that i thought I was good it ran great all day untill I was down to about a 1/4 tank then it started to act like water again , it would runWOT the rpm's would die untill I would back the throttle off and let the motor ketch up then would be fine for about a 1/2 mile or so then it would start again. I did notice that when it did die off the primer bulb was emty not hard or deflated. So at this point I am not sure if my problem is water , airleak on the fuel line , or the fuel pump. Anything would help.

Re: Fuel Problems

Fuel, being lighter than water, will float at the top of your tank. Using a short piece of hose, take a sample from the tank, put it in a glass container and let things settle - any water will be obvious at the bottom. If no water in the supply, install a clear hose from the Racor to motor. Crank the motor and look for bubbles in the clear line - bubbles = air intrusion. If you have bubbles you'll need to check all lines and connectors/fittings from tank to Racor and replace the leaking culprit. While you're at it, take a peek at your pickup in the tank - it could be clogged. Have you checked the fuel pump and undercowl filters?

Re: Fuel Problems

The bulb sucking flat is just the Racor filter full and plugged up. It won't pass water even if it's full, but it won't pass fuel either.

Your best bet is to pump off any unused fuel and burn it in the family bus. Another solution would be to get non-alcohol gas. Many places you can get it at 91-92 octane for off-road and classic vehicles. You don't need the octane, but it doesn't hurt anything either.

If water is getting into the fuel through a leaky gauge fitting, fill fitting, or poorly installed vent, that problem should be addressed anyway. Gasohol usually won't separate unless there's water introduced into the fuel from the outside.

I used to get a little water in the gas through my vent fitting, which would get flooded by a large wake from behind the boat, either mine or someone elses. A Racor fuel/air separator that I put in the vent line to solve a fuel spillage issue seemed to help the water intrusion problem as well. It took some imagination to configure it in a bass boat, but I got er done.

Re: Fuel Problems

I think I have the water under controll for now .I think I was dealing with 2 problems not just one. I am thinking my latest problem is either pump or air leak in the line between the racor and the tank. I will check the inline filter under the cowl but when I pull the off of the filter and squese the primer bulb gas comes rigt out of the fuel line so it seeme like the that filter should be fine also ,correct? I did check the screen on the pump and it was clean so I do not think that dirt is the issue, so that takes me back to the possible air leak right? Would it run fine at lower rpm's with an air leak.

Re: Fuel Problems

It'll run fine at lower rpms with a fuel delivery issue. At high rpm's a serious fuel delivery issue will cause it to balk. A marginal fuel delivery issue could make it throw parts at you at WOT.

Re: Fuel Problems

Yep it will run ok at idle through mid rang but when I crank it up for long peroids of time it acts like it is running out of fuel, and the primer bulb is emty but inflated so probly sucking some air. You saying that it will blow up?