Gas Tank Won't Fill, HELP!

[HawkTX]

My fuel gauge was showing half full and went to the fuel dock on Sunday to top it off and the guy said it took a gallon then started spitting fuel out like it was full. We both tried, but it just kept spitting fuel out like it was full. I know the tank was only half full so am I air locked? I noticed the little cap next to my gas cap that has a allen wrench hole in it. Is that something I would loosen to fix this? I didn't have an allen head wrench on me at the time nor did I know what size to use. Thanks in advance for any help.

 

[sysinu]

The allen wrench hole is your gas tank breather. That is where fuel should spit out if you overfill it, so if you're pumping gas into your tank and after a gallon it comes back up the inlet then yes, your breather is plugged. I've never cleaned out a breather on a yamaha before, I don't really recommend using a pipe cleaner brush or anything until you have a large enough opening to get the debris out of (you don't want crap in your tank).

Easiest way to test is to pressurize your tank with a little air, you should hear air escaping from the vent. If you're putting a gallon into your tank, that's a lot of pressure/air displacement and you should hear the air escaping out of your vent.

 

[0627Devildog]

Whatever you do, don't inspect the fill hole with a match. . . . . otherwise you might @Detonate .

 

[PEARCE]

Tom, you may have an insect that's decided to make a home in the opening of the breather tube. Try a little water and a brush to clean it some. Then try the air trick too and see what happens.

 

[HawkTX]

Sounds good. I will try this and report back. Thanks guys.

 

[Murf'n'surf]

Sounds like the vent tube is pinched somewhere. Follow it from the tank to the vent and make sure it's not kinked.

 

[HawkTX]

The allen wrench hole is your gas tank breather. That is where fuel should spit out if you overfill it, so if you're pumping gas into your tank and after a gallon it comes back up the inlet then yes, your breather is plugged. I've never cleaned out a breather on a yamaha before, I don't really recommend using a pipe cleaner brush or anything until you have a large enough opening to get the debris out of (you don't want crap in your tank).

Easiest way to test is to pressurize your tank with a little air, you should hear air escaping from the vent. If you're putting a gallon into your tank, that's a lot of pressure/air displacement and you should hear the air escaping out of your vent.

@sysinu So I plan on doing this either tomorrow or Sunday. How exactly do I blow air into the tank. Should I use an air compressor and go straight through the inlet where you put the gas nozzle? I plan on doing the vent line too but disconnecting from the tank and blowing up out through the vent hole. Any details would be appreciated.

 

[Lspeedss]

I imagine that if you pull the vent tube to clean it out.. Your problem will be fixed.. The only suggestion for blowing air in the filler neck would be to confirm your vent clog. To blow air just take off your cap. Take a deep breath. Put your mouth on the filler neck opening and blow. If no air comes from your vent and comes from the filler neck after you remove your mouth..its confirmed.. Clog city.
Steve

 

[txav8r]

The new boats all have an EPA canister and vapor recovery system, that will close a valve and prevent filling if the back pressure increases. It could be that valve or the breather causing it. The first time I tried to fill the boat, it prevented me from adding much. I had to use the gas down below half to get it to fill again. I haven't had any issues since. Kinks and a plugged vent would be my first place to look as well, but beyond that, it may be that damn vapor recovery system.

 

[HawkTX]

@txav8r / Mel, I saw that behind where my battery is. I think your right because I have only noticed this problem when I am at about half a tank. I'm kind of a freak about being on a full tank. I tried everything last night with no prevail so I'm going to run it down below to a quarter of a tank and then try to fill it.

 

[HawkTX]

Well. Finally got a chance to check the hoses and everything seemed in order so took her out for a spin and ran her just below half a tank and went to the fuel dock and she filled up with no problems. Crazy stuff, but all is good.

 

[Lspeedss]

Crazy stuff indeed.

 

[Todd]

I have been fighting with this on my 2013 limited. I had to disconnect the vent line at the tank to get it to fill at the lake Labor Day weekend. Got home and disconnected the charcoal filter thinking it was plugged or filled with gas since we surf with ballast and the boat leans on that side. There was water trapped on the outlet side. Drained and works fine. If this continues to happen while surfing I will bypass filter.

 

[HawkTX]

The fuel dock guy was telling me how common it is. Not just with Yamaha's, but all boats. Especially the big ones. I've only owned one other boat and never ran into this.

 

[Todd]

My Yamaha dealer said if you keep trying to top the boat off fuel can get into that canister and plug it up. I told them I don't. That thing costs $250. I'm getting ready to put it up for the winter. Bummer!! But will be watching this closely. Starting to think about getting the snowmobiles ready for some wintertime fun.

 

[PEARCE]

Do all these problems pertain to the CARB equipped boats? I've never had this kind of issue with my '06. I wonder if there's so sort of a delete option like there is for certain diesel trucks.

 

[HawkTX]

This happened again today. I disconnected the vent hose from the gas tank and still no luck. I'm at a quarter tank. Any thoughts? I've got a 2013 AR240. It's got 39 hours on it. Back when I used to trailer it I never had a problem filling it up even when the tank was almost full but I don't see how filling up on the water has anything to do with it? I really hate to have to put it on the trailer and take it in to the dealer, but I may have to. I think it has something to do with that vapor recovery system. Has this happened to anyone else?

 

[HawkTX]

I'm going out there tomorrow and see if I can run a siphon hose down the fuel line and see if there is anything clogging it. I can't imagine it is air locked because I checked the vent line and disconnected it from the fuel tank and ran air through it and it seemed fine. I'm totally stumped. If this doesn't work the next step is loading her up and taking her to the dealer. What a pain. I'll keep everyone posted in case this happens to someone else.

 

[HawkTX]

@Julian Could one of the MODS change the title of this thread to "Gas tank won't fill" instead of "Air Lock". I ran air through the vent lines so I don't believe that is the problem and I won't others with this problem to be able to refer to this thread once I find the issue. Thanks.

 

[robert843]

This is a stupid question maybe so please dont bash me for asking but there is reason behind it. When having this issue at the fuel dock have you tried filling it very slowly? The reason I ask is you mentioned not having an issue filling on the trailer. Most car gas pumps have very low pressure compared to the ones used at marine fuel docks since marine fuel dock consistently fill boats with well over 100 gallons of fuel the are designed to pump faster. I had this happen several times at my fuel dock not with the yamaha but my other boat and what I found was the pressure from the pump at the fuel dock was to much and was send fuel back up. If I pumped it slowly it would take. I never had the issue at a car fuel pump as the pressure wasn't strong enough. Once again this was just my solution so hopefully it's that simple for you but it maybe something more.