How to Stop Fuel Splash Back And Overflow At The Gas Station Pump Nozzle.

Posted by Dustin Squires on Jul 25th 2018

A anti splash valve is a one way valve that is located in the fuel fill inlet hose that stops fuel from comming back up the hose when filling the tank.

Some vehicles come from the factory with certain flaws. These are problems with the vehicle that were not caught before they left the factory, One of these is fuel pump spit back when fueling. You know? Like that annoying time gas sprayed out all over you when you were at the gas pump refueling your jeep wrangler or dodge durango?

This blog will show you some options to curb fuel overflow at the gas pump. Filler Neck Supply Co. has a few solutions that just might be the remedy you have been looking for.

To start; We will look at the Perko Anti wellback valve that was originally designed for the marine industry. This is a small flapper valve that fits inside of the rubber hose portion of the fuel filler neck. This unit goes more toward the tank end of the fill neck assembly. See a photos of this item below.

This anti back splash unit is a one way valve that allows gas to go in one way, and not come out the other. At this time this valve only comes in 2 sizes 1-1/2" and 2" outer diameter. You will need at least 1-1/4" length of space inside the hose to install this valve. For All other sizes you will need to build an assembly that incorporates: The Perko Anti Wellback Valve, A section of hose to house the valve and Male Reducers on each end to allow you to hook up smaller diameters of hose. See bottom photos.

On the left you can see the valve itself....On the right you can see the unit when it is installed inside of the hose.

You can see the whole assembly below used for 1-1/4" and 1-3/4" Hose Sizes. The Valve is nestled in between the reducers inside the rubber section of hose. A minimum of 5" section of hose is necessary. The total length of the anti fuel spitback assembly is about 6" long (not including the ends the hose slips over). Total length is 10" not installed.

Below is an overview of the total parts needed to build a anti spitback unit for sizes 1-1/4", 1-3/4" (this unit does not work for 1989-1997 F series pickups because of filler neck design.