Sea Ray

Welcome to the forum.

My assumption is the issue is fuel burping back out the fill port during fueling, not fuel discharging within the hull, between the tank and filler connection.

If there is internal fuel leakage, then locate the issue and correct the problem immediately. Do not wait. Do not operate the boat prior to resolution is fully verified.

If the fuel has unacceptable burping back out the inlet during fueling, then check the fuel and vent hose routing. Both should slope downhill from the hull to the tank, w/o dips / droops.

If that routing doesn't currently exist, then modify the routing to determine if that resolves the problem.

On my boat I will get burping only at the very end, so I also use the audible detection described by Airwaves to know when to stop, prior to creation of a mess. In my case slowing doesn't help at the end, I just stop immediately prior to full.

Airwaves--yes, I definitely have to listen to the sound to know when to release the trigger. Thanks!

Wingless--It burps back out of the vents and the spout--the latter is like a tsunami. There is a dip in the lines, but I think the problem is with the hose fitting attached to the tank. It has a 90 degree bend in it, and I think that's where the air lock happens. I understand it's not uncommon on this model
sea Ray, and curious if anyone has had and fixed the problem. Happy new year all!

wingless: "If the fuel has unacceptable burping back out the inlet during fueling, then check the fuel and vent hose routing. Both should slope downhill from the hull to the tank, w/o dips / droops."

Flip: "There is a dip in the lines"

The fuel hose and the vent hose MUST both slope downhill to the tank.

My suggestion remains to change the hose to eliminate the dips and droops as the first step.

Copy Wingless. I'll have a look at the lines again. Thanks!

Given the size of your boat I am presuming that it is diesel. Most fuel docks have high speed nozzles wich causes the diesel fuel to foam when filling up. I would advise you to slow the nozzle down when you feel you are getting close to full to let the foam settle out. It is generally the foam that is erupting like a volcano from the fuel fill. They make a whistle that can go in your vent line to indicate when you are getting close to full also.

Yes, I have the cummins blue diamond diesels. Unfortunately even the slowest nozzle speed causes the backsplash in less than a minute. It takes up to 20 minutes to fill each of the 200 gal tanks.

I have a 95 440EB same issue. When fueling it spits out the vent.(even at a slow flow) I raised the vent hose, it help. It was also recomended to increase the diamiter size of the vent hose.Flip, I got you beat on the fill time ....19mins per side.

Gotcha!

Had the same problem. It was caused by the vent being stopped up. Spiders or other bugs get up there and clog the vent. Take a small wire and run it up the vent from the outside. Bet it solves your problem.

I have a 2002 460 and encountered the same problem. I stumbled onto a solution that has worked now for two seasons. It is simple: when fueling open both of the fill caps and keep them open until you have finished fueling both sides. I do not know why this worked for me but it surely did. I was about to modify the vents with a gizmo but now not necessary.

You know, I don't know why either, but I bet you're right. My mechanic ran a crossflow line between the two fuel lines and the plan is for me to make sure I have both fuel caps off when refueling. You're giving me added confidence that this will solve it. Thanks!