Water getting into gas

iggyw1

Master Chief Petty Officer
Joined
Oct 24, 2011
Messages
880
I had water in my gas tank twice this season. The first time was when I washed the boat spill tray off at a campsite after I parked under a tree. I used the water hose at the clean out station for this. The spill tray is the rear deck of the boat where the gas filler cap is located. The second time (yesterday) was when I drove home from the boat launch in a real heavy down pour the day before. I went out yesterday and the gas had water in it. I did an emergency surgery on the motor out on the lake draining about one gallon out from the motor gas line while I squeezed the ball. I put the gas I drained into a 5 gallon bucket, and the bottom 1/3 of it was clear (water) looking thru the side of the bucket. The gas is blue because I have a two stroke with oil in it, so I can see the definate difference thru the side of the bucket.

Now my question: Looks like the filler cap is o.k. It is a black plastic cap and flange. The tube going into the gas fill hose is a shiny metal, as are the threads that the plastic cap screws into. The threads on the cap seem o.k. as well as the threads on the metal filler tube. There is NO GASKET or "O" ring between the plastic cap & the metal threads. Is there suppose to be? I cannot recall if there was ever a gasket at this point or not. How hard is it to remove the three screws from the flange and take the thing out and just replace the entire tube with a new flange and cap? Will I have a problem getting the metal tube out of the fuel fill hose? I cannot get under the back deck to have a very good access to it. Has to be done from the top for me to do my own, Thanks!
 

Baylinerchuck

Commander
Joined
Jul 29, 2016
Messages
2,726
Not sure about the gasket, but to your question on the fill hose. It can be nearly impossible to get the hose off the tube without cutting it. Gas cap would be my first suspect.
 

iggyw1

Master Chief Petty Officer
Joined
Oct 24, 2011
Messages
880
What about the vent ?

I thought about that too, but all I can do with that was to unscrew the vent from outside of the hull on the boat. Cannot get to the backside of it because it is between the hull (side of the boat) and a live well that is inside. If I had to, I suppose I would have to get that livewell out, but that would not be a choice that I would want to make unless it is absolutely completely necessary. I have ordered a water separator (today) and when it comes in, I will be installing that and hopefully that will help and solve my problem, but I was going to first try to remmedy the cause if it was something I can handle.

When I did unscrew the vent from the hull, I looked at it and the baffle is in place and not damaged, and it looked good. The opening with the baffle was pointing down like it should be (as far as I know) and it is pretty much above the water line on the boat.
 
Last edited:

iggyw1

Master Chief Petty Officer
Joined
Oct 24, 2011
Messages
880
Not sure about the gasket, but to your question on the fill hose. It can be nearly impossible to get the hose off the tube without cutting it. Gas cap would be my first suspect.


Can I replace the gas cap and the flange alone without removing the metal tube tha the flange surrounds? There are three screws that I can remove holding the flange down. I don't know if I can take them out and pry up on the flange to replace it. The cap is attached to this flange with a rubber retainer so the cap will not get lost. Thanks.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
47,482
post a pic of the cap and the screw flange. there may be an o-ring missing. I replace the o-ring on mine every 4-5 years as the old one simply fails from UV or ozone or something. it usually fails when I pull the cap to fill and the o-ring pieces fall on my shoes. I have extras in the glove box of the truck for that reason (I also have extra brass plugs for the transom)
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,473
No reason to replace the entire assembly. Buy a new cap or just replace the o-ring. Common part to fail
 

iggyw1

Master Chief Petty Officer
Joined
Oct 24, 2011
Messages
880
I will replace the "O" ring or gasket, but I just did not know if it ever had one on it or not. I just never noticed whether there was one or not. I do not know the first thing about posting a picture, sorry. It has a plastic gas cap that is threaded into a silver filler tube that is most likely inserted down into the fill hose to the tank. It is all under built in live wells and in the bilge area where I really cannot get to so easy. I am thinking if there is a gasket missing that goes on the cap, that would be my problem.

Anyway, I have a water separator on order and I should have it in a few days, so I hope it will serve me good. Thanks for all your input.
 

fishrdan

Admiral
Joined
Jan 25, 2008
Messages
6,989
This type of filler?

m9nvxvdzCpj8cPuV8Qw3b-g.jpg

Look at the pic closely, there is an O-ring at the bottom of the cap. Sounds like your water issue if it's missing.

As for removing the entire filler housing (metal part) it's going to be a royal pain as the hose is very rigid, reinforced, and formed to the fitting after years of being clamped to the housing. I bought a section of the filler hose and the boat shop used a chop saw with an abrasive wheel to cut the hose, it's that tough...
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
47,482
Go to your local ACE hardware, walk into the plumbing section, get an o-ring that fits tight on the cap as everyone has been telling you. Buy two, put one on the cap, put spare in the glove box.

Go boating
 

iggyw1

Master Chief Petty Officer
Joined
Oct 24, 2011
Messages
880
This type of filler?



Look at the pic closely, there is an O-ring at the bottom of the cap. Sounds like your water issue if it's missing.

As for removing the entire filler housing (metal part) it's going to be a royal pain as the hose is very rigid, reinforced, and formed to the fitting after years of being clamped to the housing. I bought a section of the filler hose and the boat shop used a chop saw with an abrasive wheel to cut the hose, it's that tough...


My cap is very similar, but it does not have the raised lip around it. And mine does not have a gasket, so I will get one. I will get a flat gasket as apposed to an "O" ring. Did not know whether a gasket was required or not, hence my question. Thank you all for your input. I will get a gasket to fit it and I will buy a few spare ones too as I did long ago for my transom drain plug. Please consider this case closed, and thanks again.
 
Top