fuel venting.

[grillman6211]

2012 Starcraft Starfish 176 with Merc 90 4 stroke
When fueling, gas backs up through the filler tube, no matter how slow I pump it in. The boat used to have a kicker motor installed, but it was removed. There is a fitting in the splash well that is sealed with a bolt. As there is no other visible vent located on the boat, could this be the vent?

 

[wired247]

Re: fuel venting.

Yes. Thats the vent for the gas tank. You need it.

 

[grillman6211]

Re: fuel venting.

Thanks for that!
I wasn't sure if that was a vent, or just a fuel supply for the kicker motor. Next question, with the location being in the splash well, isn't there a good chance of water getting into the fuel? Is there some kind of cover or cap for this fitting? I bought this boat used, and have never had to deal with a kicker motor issue before.

 

[roscoe]

Re: fuel venting.

Hey there grill man, welcome to iboats.

The vent would NOT be located in the splashwell.

And no fuel line should be "sealed" with a bolt.

Your fuel tank vent, will be located on the outside of the boat.

The extra fuel line that supplied the kicker, should be removed.

 

[spoilsofwar]

Re: fuel venting.

The boat's vent may well be integrated into the filler port and not a separate fitting located elsewhere. That's how many boats come now; mine is one of them. Trace the vent line from the tank to the hull and see.

 

[grillman6211]

Re: fuel venting.

Thanks for the info. There is no vent on the outside hull, so if the fitting in the splash well was just for the kicker motor, then I guess I'll keep it capped off.

 

[eggs712]

Re: fuel venting.

Both of my boats have fuel tank vents that go into the splash well; it is not uncommon.

 

[grillman6211]

Re: fuel venting.

Thanks eggs 712, some very different answers. If my vent is incorporated into the filler tube, it's a very poor design for a 2012 boat. When I fill up, it has to trickle in, or else I get fuel splashing all over. Not new to boating, just new to this boat, it's light years ahead of my previous 1987 Starcraft.

 

[roscoe]

Re: fuel venting.

Very easy to see if your vent is incorporated into the fuel fill.

You should be able to see it by looking into the neck of the filler.
Its either a straight fill tube, or it has a small hole near the hinge area of the cover.

To check if the vent is clogged, causing your filling issue:
I believe if you remove the speaker just in front of the filler, you will have access to the fill and vent hoses on the bottom of the fill plate.
Remove the vent hose and inspect for obstructions or kinks in the hose.
Hopefully, you will find the issue right there.

You should also have room to mount a conventional tank vent, just below the filler plate.
You would need to replace the filler plate with a non vented one, to prevent fumes from building up under the decking.

New fill plate and vent would cost about $60, if you do it yourself..

 

[N3UP]

Re: fuel venting.

Are you fueling on the trailer?

I have a problem with fuel blowback on my boat. I have verified that my vents arent blocked, and i have noticed that I only get the blow back after the tanks are about 2/3 full.

I suspect that my issue is that the vent lines connect to the forward end of the tanks, and when in the water my boat has a somewhat stern low attitude, but when on the trailer it is level or slightly bow down.

When I get ready for the season (if all this $&^%! snow ever stops) I am going to try to raise the bow when fueling to see of it helps.

 

[grillman6211]

Re: fuel venting.

Fueling is done while on the trailer. The boat sits almost perfectly level on the trailer with a slight bow up position. Even when I fuel at the marina, the boat is fairly level, but I still have to trickle the fuel in or I get splash back.

 

[JoLin]

Re: fuel venting.

Just occurred to me- I have a 16' Sylvan fish 'n ski that I'm fixing up. The 24-gallon tank is roughly 4 ft long and 2 ft wide, but very shallow (6-8 inches deep). My tank has TWO vents- one at the front and one at the rear.

If yours has only one vent, the fuel coming into the tank may block it well before the tank is full, depending on the attitude of the boat when you gas up. Just a thought.

 

[Auger01]

Re: fuel venting.

If a fuel tank doesn't have a vent, it will either collapse as fuel is used or starve the engine of fuel. Since you have indicated that the boat doesn't have a vent, which does it do?

 

[grillman6211]

Re: fuel venting.

Since my fuel tank is internal, I wouldn't be able to see if it is collapsing. The engine does not act like it is starved for fuel, so according to the previous answers that I have recieved, the vent is built into the fuel filler. It must be a small vent and/or the filler tube must be at an extreme angle, because the only way to add fuel without getting splashback is to trickle it in.

 

[Teamster]

Re: fuel venting.

The vent hose may have a kink in it,....