99 Seafarer 228 - water in fuel

[Dagonit]

Help - any suggestions would be great. I have a 228 Seafarer 1999 model - upgraded to 4 stroke Yamaha 250 a few years ago. I keep finding fuel in the water. I have a water separator located just beyond the fuel tank selector that I try to check often (to prevent the alarm going off and having to remove cowl from motor to empty cup on motor) - I just cant figure out how water is getting in. I have had fuel pumped out previously (both tanks) and had main tank cleaned. I have new o rings on the fuel fill caps. I have removed the tank covers on the floor board to look at and take photos of tops of tanks. They look good - damp but good. I do not smell fuel. The boat stays in the water and there is no sign of a fuel leak. I cant help but think I may have a pin hole or something on the top of the tanks.... How do I find the leak? Do I attempt a pressure test? I understand replacing the tanks is a serious undertaking.
I use marine Stabil and have used yamalube Ringfree in the past.
Is there a fuel treatment you recommend for getting rid of the water? Is there a way to determine if it is salt water or rain water getting in?
Thank you for any suggestions. DAG

 

[seasick]

First of all, if you had leaks on the bottom of the tank, you would smell gas and you don't. Leaks on the top are less common but a leaky sender or sender gasket can allow water in. However, if there is a leak like that, when the tank is full, gas will also seep out and you will smell it (assuming your nose works. Mine doesn't!)

Is the tank vent built into the fuel filler fitting ( combo fill) or is the vent on the outside of the hull?

Water in the tank is more often than not in my experience due to leakage around the gas cap. You did check the o-ring you stated but check again and make sure it is the correct ring. Check the fitting and cap for cracks.
Second common cause of water is a bad load of gas. Where do you get gas? I avoid getting gas in the spring at fuel docks that don't pump a lot of gas during the winter. I wait a week or two for others to fill up. If there is water , they will break down and not me

When you get the water alarm, you say that you drain the clear bowl. Is it clear and do you see water in it? (there may be a red float ring indicator) I ask because the water alarm circuit can act up and sense an alarm when there isn't one, so to be sure you have water, drain the gas from that bowl into a clear jar and let it sit for 15 minutes or so. If you do have water in the bowl, you must also remove and drain the water separator. If you have the type with the clear bowl and drain on the bottom, you should drain the bowl. If you just have the filter, drain that too into a clear jar and let it sit.

One more thing; How were the fuel tanks drained and the main cleaned? Were the senders removed and the tanks drain through that opening?

 

[seasick]

One more thing, run on the same tank for now, probably the main. That might help determine if the water is in one tank only. If you run into the proble, go through the draining process I mentioned and then switch to the other tank and see if the problem pops up again. If it doesn't you have an issue in one tank.

 

[SmokyMtnGrady]

Take a quart Mason jar and put fuel in it from your source. Let it sit and see if water is on the bottom of your jar. If yes, you know how it got in.. if no, then either it was a bad slug of fuel or it is on your boat some place. Check gas cap per seasick.

 

[Dagonit]

Seasick & Smoky -
first thank you for the input. I will get answers to your question this week and get back to you. I need to confirm how the fuel was drained last time.
I think the o rings on the fuel caps are the correct size but will confirm.
I will get back to you ....
thanks

DAG