I use regular car gas stations to fill up my cobalt but it always tends to splash out of the fill hole and the side vent even before I'm able to fill the thing. Never happens when I use a gas station on the water however.

What's going on? Any tips on avoiding spillage at car gas stations when filling up my boat?

Mine will BURP and entire gallon onto the ground if I'm not careful, but only when the pump clicks off or shuts off at the 50 or 75 dollar max, I dont think the vent is large enough... I can usually hear it comming now, I just listen to when it starts backing up the fill line and slowly back down and I can usually avoid spilling..

I can usually hear mine too, sounds like a rush of air coming up the vent. If I slow the pump I can get another 5 gallons in it. My boat sits with a "bow higher" additude when on the trailer. The filler and vent are located at the back of the tank, so it will be "full" but still have a pocket of air in the front of the tank. It sits level in the water so I don't have the same problem when fueling at a marina.

i had that happen to me, and found the vent was pluged with wax cleaned the vent and problem solved

Install some of these, I put them on my boat and it just about eliminated any problems I had with the fuel spilling.

http://www.shipstore.com/SS/HTML/RAC/RACLG100.html



LIFE GUARD 100 Gas - Diesel - Fuel/Air Separator Filter
Manufacturer: RACOR - Parker Hannifin Corp

I have always wondered why boats don't have the vent tapped into the filler like cars do. Then just a simple vented gas cap. Then the pump would shut off automatically before the gas spit out of the vent. Seems like 3 out of 10 boats filling up at a marina will spit some fuel into the water from the vent.

my approach is never have enough money to fill it up half tanks as far as i get

Yea its getting worse, Ive got one manufacturer thats charging 25% freight/shipping container/fuel surcharge etc on top of the cost

Just bought a drum of race fuel $650

Clearly the boat is sensitive to the angle it is sitting when filling. On the water it's ass-down which is helping you fill the tank before the gas burps out the vent/fill. On land and sitting on the trailer it is more or less flat and getting to the vent/fill quicker to slosh out.

All my Cobalt's all did this...it was a pain! The only way I could fill it on the trailer is to go slowly. But when trying to pump 50+ gallons at a trickle pace people were not happy with me waiting and waiting and waiting.

If you dare, you can always disconnect the trailer at the gas station pump, crank the trailer tongue jack to the moon and simulate a bow high attitude. Maybe that fire drill will get your boat filled with less pain.

I use these in my boats. They work well if mounted vertical or nearly so. They have other models as well.

https://discountracor.com/shop/fuel-...air-seperator/