It might sound strange but you need to repair your front tank by replacing fuel pump assemly to stop this overfilling. The problem is that check valve(s) in this assembly are stuck allowing fuel to get in there.
There are three ways to do it - good one, bad one and russian one
I'm a noob around here but from a little searching the last few days i've come to the conclusion that you'll either replace your fuel filter in the take its draining into. Or the just cap off your problem tank, which you'll find lots of pretty detailed posts in past threads.
I know in my situation I'll be capping my rear tank since my front has been draining into it. I only use my front anyways.
Thanks for the responses. I would like to cap off the front tank... it would get rid of a lot of headache. I wouldn't need to worry about the valve or pump either. But I do not know where to find how to do it.
Probably searched 100 pages before I found a good one.
good luck to you
Here's a better write up
I removed my front tank from my truck and in my instructions I mention how to cap the lines off. The rear lines are at the same Y connectors as the front ones. Simple to do!
The process of removing the tank is fairly simple; Here is the steps:1). Gather the list of parts you will need to cap off the fuel lines;
2- 3/8" x 1" Hex head bolts. 1/2 inch Hex head (Hardware Store)
1- 3/8" barb fitting with 1/4" threads on opposite end. (Hardware Store)
1- 1/4" Cap that screws onto the barb fitting. (Hardware Store)
3- 3/8 to 1/4" hose clamps. (Hardware Store)
Small tube or packet of RTV Sealant (Walmart or Auto part store)
Total cost $8.00. unless you have a few of the items already around the house.
I would recommend that you wear rubber surround safty googles before going under your truck ( the ones that look like motorcycle goggles) in order to prevent gas splash from getting in your eyes, along with dirt and rust. I keep a pair in my truck at all times.
You can protect your skin if you feel safe that way, this process doesnt take long so any short exposer of gas I dont threat.
There will be gas remaining in the lines that will run out so make sure that you have a few old rags and newspapers at hand.
2). Pull your vehicle to the area of which you will be working and DO NOT TURN OFF THE IGNITION but instead reach under the drivers side dash and locate the inertia switch, it should be mounted to the inner firewall, to the left of the brake pedal or to the right of the kick panel depending on year and type of vehicle. The top of inertia switch has a slot just under the trip off/push on button in which you slide a flat head screw driver into and pop up the botton of the switch cutting off the fuel to the lines. This will cause your truck to spit and sputter until it burns off the gas that is still pressurized in the lines, then stall out. To do this is important unless you plan on a gas sprinkler system when the fuel lines disconnect. I then also removed my gas cap from the tank i was removing to further insure no surprises of unexpected gas flow.
Once it has stalled, you need to chuck the tires and jack it up in the front and back on the tank side and place jack stands under it allowing enough room to crawl under and remove the tank, unless you have a 4x4 that already gives enough clearance.
3). Take the same jack that you lifted your truck and place a piece of wood across it. (unless you have a transmission jack) Doing this will help balance the weight of the tank which is only around 50lbs empty. Place the jack under your tank to where the board is between the two tank brackets holding the tank up. Lift the tank just to the point of releasing the weight off the brackets.
There is only one 1/2 inch head nut and bolt per bracket holding the tank. You will find them along the drive shaft. NOTE: Loosen these front and rear bracket bolts to the lowest safe point without removing them. This will give the tank enough slack in the brackets to be tilted down on the drive shaft side allowing just enough room in which you can then reach above the tank to disconnect the wire harness. Do not cut these wires if you can later use the pump as a spare. I beleave it will also fit in the rear tank.
4). Now is where the mess begins; NOTE; These lines are plastic covered over with rubber hose in areas. There will be two fuel lines running to the top of the fuel pump. With a rag at hand to catch fuel; disconnect these two fuel lines by using a flat head screw driver to pop out the retainer ring (or hose clamp) that holds the line to the nipple, then carefully pull off the line. Do not worry about marking these lines as incoming and outgoing because it is not important unless you are planning on putting another tank on it. (If not planning to reinstall another tank then you can just cut the lines in half at the nipple) There will be a larger line towards the center of the tank which is just a tank vent line. This line connects to a vent plug that installs into the top of the tank and will also have a connector to hold it on. disconnect and pull it up from in the tank.(No gas with this line)-(Again you can also cut this line if not planning to reinstall another tank). You will also have the filler neck to disconnect which will connect with a hose clamp.(Again you can also cut this line if not planning to reinstall another tank). These three smaller hoses will be cut off again once the tank is out of the way giving access to the 3 (Y) hose connectors.
Once these hoses are disconnected from the tank, check to see if the jack is supporting the tank well enough to disconnect the bracket bolts completely and swinging the brackets down and turning them forward to remove them from the frame. Slowly lower your tank to the ground and slide it out from under.
(The rest Is a cake walk)
5). Now that the tank is out of your way and you have access to the 3 (Y) connectors. you will spot them on the inside of your frame about a foot or so behind your fuel filter. Once you find the 3 hose (Y) connectors (2 small and 1 large), you want to re-cut off the lines that you disconnected from the tank about (VERY IMPORTANT) 5 to 6 inches to the rear of each (Y). Leave enough rubber hose to cover all the plastic inner hose except about a inch or so. This will help protect the plastic hose from damage. These 5+ inch hoses will be where you want to cap off at.
Slide the 3 hose clamps over the 3 hoses that were cut next to the (Y) connectors for later tighting.
Coat the threads of the 2- 3/8" x 1" Hex head bolts with RTV Sealant. With a 1/2" socket screwdriver and good bit of pressure, Screw the hex head 3/8" x 1" bolts into the open ends of the 2 smaller plastic gas hoses. This will be a tight fit so use enough pressure to keep them threading forward and not strip out. The plastic will expand enough to allow it to thread without tearing the plastic hose. Once you have at least a half inch or more bolt threaded into the plastic hose, slide down your clamp and tighten it securely to the end of the hose over the installed bolt. Do not over tighten the clamp because you dont want it to cut into the plastic. Then slide the rubber protection hose down to meet the clamp. Same procedure for both smaller gas hoses.
Now for the Venting hose: Coat the 1/4 inch threads of the barb fitting and 1/4 inch cap threads with RTV Sealent. Screw the cap tightly onto the barb fitting. Smear some RTV Sealant onto the barb side of the barb fitting and insert the barb fitting into the rubber Vent hose as far in as possible. Then again, slid the hose clamp down over the inserted barb and tighten it securely.
You may have already noticed that the filler neck hose is double ply. I have no explanation why this is but its not important. I cut filler neck off shorter so it would be up out of the way.
For the wire harness connector; I did not remove it. I just wrapped the entire connector with electric tape down to about 4" because I was wanting to find away to jumper the wires to fool the computer in case the computer since that the pump was disconnected and throw on the check engine light. It never through the light (Then again, I never flipped the switch over to front tank ether) so I just fastened it to the top of the cross frame rail so it would be out of the way. That pretty much raps it up. ((DON'T FORGET TO RE-PUSH THE BOTTOM DOWN ON YOUR INERTIA SWITCH)) under your dash. I forgot to do mine and thought I messed something up Lol!!! Only thing left is to clean up.
I did forget to mention one thing that is important in this write up. In order to get a nice clean rounded cut on the fuel lines that will be plugged. I used a regular strait blade utility knife, with a new blade in it. The plastic fuel lines aren't as durable as they look, The utility knife cuts through fairly easy. Now also keep in mind that these lines will smash and crack, so try not to handle them with pliers.
Went straight threw Maryland Vehicle Inspection with tank removed, was only told that I would have to have a locking gas cap for this tank filler-and not carry it on my key ring. So not to put gas in accidentally.