How do you know if there's water in fuel tank?

[High Cs]

In a prior post about fogging a MPI engine it was said that a new fuel filter/water separator should be used so that if water is found it wont rust in the filter. Also if any, or too much, water was found that that would be the time to get it out of the tank before it caused problems.
My question is: After pulling the old filter (full of fuel) how do you determine if there is water present and, if so, how much?
And, as long as we are talking about it, if it is found to be excessive then what is the procedure to rid the tank of water?
I don't have a fuel problem, just want to make sure I don't get one. The only preventive measures I take is to add stabilizer at the end of the season and try to keep the tank full the rest of the time - not an easy task I might add.

 

[chiefalen]

Re: How do you know if there's water in fuel tank?

Dump the contents in a clear, clean container.

Oil will float on water let it sit for a hour. Tell us what you see

 

[Don S]

Re: How do you know if there's water in fuel tank?

My question is: After pulling the old filter (full of fuel) how do you determine if there is water present and, if so, how much?

I dump the contents of the old filter (always) in a clear container and look for water/rust/gunk in the fuel. It settles to the bottom almost instantly.

If more than a tablespoon full or two is present, it's time to get the water and gunk out of the tank.

 

[JustJason]

Re: How do you know if there's water in fuel tank?

they also have a paste that you can smear on a stick or dowel. If you have good access to the tank you can drop the dowel in and if there is water in the tank you'll see a line on the dowel showing you how much.....
The clear cup works just as well though.

 

[High Cs]

Re: How do you know if there's water in fuel tank?

So I find a suitable container - this took a while cause the "Admiral" wouldn't let me use any of the clear "things" I dound in the cupboards, we finally agreed upon using a vacant mason jar - and I proceede to follow the directions given in the prior posts. The fuel looks dark from the fogging "blend" but no separation or "gunk" is present.
It looks like I'm good. Thank you

 

[Don S]

Re: How do you know if there's water in fuel tank?

we finally agreed upon using a vacant mason jar - and I proceede to follow the directions given in the prior posts. The fuel looks dark from the fogging "blend" but no separation or "gunk" is present.

You are supposed to check the OLD filter that has been there all summer. That is the one that will tell you what the water/fuel ratio looks like. Not a filter that has been on there for a few minutes for winteization.

 

[High Cs]

Re: How do you know if there's water in fuel tank?

I guess I wasn't clear in my post. I *did* observe the fuel in the filter that was used all summer. The reason for changing the filter after fogging the engine is due to my earlier ignorance thinking that I should change it in the spring - you clarified the need to do it now so I did it after fogging.
I was concerned that looking at the mason jar full of *new* fuel that I wouldn't be seeing the true picture but can I assume that any water present prior to fogging would still be there afterwards?

 

[chiefalen]

Re: How do you know if there's water in fuel tank?

There is a way to know for sure you have no water in the fuel. Works best when boat is on a trailer and the bow is as far up as you can get it.

Remove the fuel sender door on the gas tank.

Stick a hose hooked to a cheap auto electric fuel pump.

Stick the hose all the way back in the corner of the tank bottom.

Pump the water out of the bottom of the tank, water is heavier than fuel.

Pump it into that mason jar, you will see when it starts to pump clean fuel, stop the pump and close up the door on the tank.

You could pump out the fuel pickup tube hole instead of the fuel sender door, and at the same time check the screen on the fuel pickup tube.

And make sure the anti-syphon valve is clear bye blowing thru it.

Not a bad idea to every few years do this anyway, to get all the crud out the tank, and clean the screen and check the valve.

Good luck

 

[HT32BSX115]

Re: How do you know if there's water in fuel tank?

Remove the fuel sender door on the gas tank.

Stick a hose hooked to a cheap auto electric fuel pump.

If you decide to do it using an electric pump be VERY careful of sparks from connecting and disconnecting the pump.

An easier and possibly safer way might be to use a piece of 1/2" or larger clear hose as a siphon.

With the bow up, the gage sender out, and a helper to hold the other end of the hose and switch tanks when each one becomes full, use the "suction" end of the hose to "vacuum" out the tank.

You can move the end of the hose around in the tank to the back corners to get all the loose crud. It works best if the gage-sender hole is at the back of the tank and if you use a flashlight you can probably see inside the tank to look for debris/water etc.


DO THIS OUTSIDE! don't do it in your garage near the water heater etc


Regards,


Rick...

 

[High Cs]

Re: How do you know if there's water in fuel tank?

Thanks for all opf the great information.
Upon further investigation this morning, looking at my jar of fuel, I do see that there is water at the bottom - I'm guessing about a tablespoon. That's enough for me to want to rid the tank of any water that surely must be there also.
I'm thinking that a section of hose with a squeeze bulb like on an outboard gas tank might work well (and be safe) to suck the water out and/or maybe start a siphon?
Again, thanks for the advice.