Draining water/sediment from fuel tank

[mkbb]

1997 5.7 mercruiser doesn't want to idle. It will run at high RPMs (above 2000), but dies when pulled back to idle. After this it is difficult to restart and will cough out white smoke when it does eventually start. Boat has been on a covered lift for past three years with little use (3-5 times a season). However it has been maintained every season. It ran fine until 2 weekends ago when the above problems arouse. I think the problem is the result of always carrying gas containers to the boat rather than fill up on the lake (bad practice, I guess). I removed the fuel/water separator and it was full of rust colored fuel/sediment with some water. I will replace the same this weekend. I would like to know if I can use an 12 volt oil changer to drain some of the fuel from the tank to a container without blowing myself up? I'm afraid that just changing the filter will not remove enough of the water/sediment. Thanks - Mark

 

[chiefalen]

Re: Draining water/sediment from fuel tank

I don't think how you get the gas in the tank matters.

Tilt up the front of the boat, take off the fuel pickup tube, Check that the screen on the bottom of the tube is clean.

Stick a hose all the way back in the corner of the fuel tank. Hook a cheap electric fuel pump from any auto store onto a clear hose Buy it at the auto store about 3-4 feet.Run from the other end of the fuel pump a hose 4-5 feet into a clean clear container till you see fuel.

Water is heavier than fuel you will see when the water stops and the fuel begins.

Pull the connection off the battery.

Keep the pump as far away from the opening in the fuel tank as possible.

4-5 feet maybe.

Than pull the hose out of the tank put pack the pickup.Check the anti-siphon valve that it is still good by blowing thru it.

Check you water seperator if you have one. And the fitting at the carb there is usually a filter there to.

Do you have a filter in the fuel pump check that one.

Post how you made out! Good luck!