Gas tank overflowing

[obsidian]

I've searched for about an hour and haven't found anything good.

First the back story.

Bought the car and the first fillup as the nozzle clicks off, fuel splashes out a bit and goes on the ground. It came from under the car.

Fuel mileage SUCKED. Talking 14-15mpgs.

Topped off again, same thing.

Then I looked back and saw a ugly piece of metal. Pulled it up (held down by orange RTV and house caulk) and look, my fuel tank. Wow the gas smell was strong. Then I noticed it was very loose.

It was held down by TWO SELF TAPPING SCREWS. Not only that, but they were on the SAME SIDE so the other side was completely loose. And it was also sealed with orange RTV and house caulk.

So I repair it. Put in a new o-ring, seal the self tapping screw holes and use the 4 original studs I had left to tighten down the fuel sending unit to the tank. Reseal any extra holes and look, no more fuel leak.

Now I'm getting 25-30mpgs (likely due to fuel not evaporating) but when I try to top off, I get nothing but back splash. The tank is being pressurized and is not allowing me to fill up even at the slowest speeds. I ended up disconnecting a small hose going to this blue canister type looking thing at the fuel sending unit to top off and it worked but what a mess I made.

Now, how do I fix this properly?

----------------

Cliffs:

1. Fixed poor work the proper way.
2. Now fuel tank is pressurized when fueling and blows fuel back out the fill when it's still empty.
3. Have to remove hose to blue canister type thing at fuel sending unit to fill up.
4. What do?

Thanks for all of the help.

-Brandon

 

[rlacasse1]

There is a vent hose on the top of the tank. Drop your tank and make sure its not plugged up.

 

[obsidian]

So that hose doesn't go to the evap canister under the battery try like I've heard?

 

[rlacasse1]

I'm not sure what hose your talking about. I don't remember and haven't had a gas tank down in a while.

But what I do remember, is there is a large hose on the top of the tank that you can't really see, and if you can you can just barely see it. It goes from the tank up to the car somewhere (if I recal correctly). And it is just a vent. It's about the same diameter as your thumb.

 

[anchew02]

funny thing i was having the same issue... shitty gas milage and very strong fuel smell.. well i found that my fill hose was cracked which inturn allowed vaporized fuel to leave tank.. i removed the fill pipe and found that there is another smaller pipe in the bigger one. mine was tweaked and and causing a backup of fuel

 

[jtmcinder]

I was getting all ready to type a long post, but then I came across this:

1. Fixed afro engineering properly.

 

[obsidian]

Good ol' afro engineering. Gets me every time. I'm still having this issue. I can't see the vent to the inside of my car as that just makes NO SENSE and I can't find it.

I guess I will pull my fill neck down/out and see if there is that little guy inside. Maybe that is my issue. Thanks for the reply.

 

[rlacasse1]

You can't see the vent while the tank is in place. You will have to drop it to see it. It is hidden at the very top.

 

[obsidian]

Alright, well, first off if I offended anyone, no harm was meant and I apologize.

I'll rephrase it as saying the previous owner should never hold a wrench again.

Now for a bit of an update, The gas tank no longer overflows thanks to some fixes I did.

When trying to fill up I would barely get anything into the tank before it would splash back out of the fill at me. To temp resolve this I would remove the small blue filter looking object on the fuel tank around the fuel pump/canister top. I firmly believe this to be a check valve.

Now I got a bug in my head telling me to REVERSE the check valve to flow the opposite direction. When I needed fuel this is exactly what I did. I still can't fill at full blast BUT I can fill it up on the slowest setting and get about $35 (10 gallons) in without a burp or shutoff.

SO MY FIX IS: take off the blue canister and have the arrow pointing TOWARDS the rear of the vehicle.

If pics are needed then PM me.

 

[Nasty Dream]

Alright, well, first off if I offended anyone, no harm was meant and I apologize.

I'll rephrase it as saying the previous owner should never hold a wrench again

I always just say jury rig/jury rigging

My reading comprehension is extremely good, but hey - it's early. Maybe I'm missing something. You had screws in your gas tank holding it on? Holes in the tank?

I saw a DSM fuel tank laying on the ground at the junk yard. I'd replace it. I'm sure it wouldn't cost too much.

It's a tank integrity thing. You can patch it but it will never be the same.

 

[obsidian]

I agree completely, but the chances of me finding a AWD tank in the yard is not good.

Also, yes, the fuel pump/canister top lid was held down by two self tapping screws on the same side and nothing.

So if you imagine a clock, the two screws were at the 7 o'clock and 11 o'clock position while everything else was caulk and RTV.

I'd like to punch the P.O. in the face but hey, this is my car now and I know things are being done right.

Hell, I got both windows working properly the other day.

 

[Nasty Dream]

I agree completely, but the chances of me finding a AWD tank in the yard is not good.

You could try. It's not a high demand item.

There are several turbo DSMs at a nearby scrapyard here. 10 Eclipse/Talon/Laser total.

 

[MY1GDSM]

Do a quick search on Car-Part.com--Used Auto Parts Market

 

[Nasty Dream]

I saw a DSM fuel tank laying on the ground at the junk yard.

I just want to say that the reason I was aware of it is because I noticed it was plastic. My gas tank is steel.

In my constant pursuit of improving the car and lightening it, I guess that it may be lighter than mine. After all, I have a '95, and there were plenty of small revisions/improvements throughout the model year. (my sun visor weighs like 2 pounds, for some reason; I replaced it with a much lighter one from a newer Eclipse that didn't use DIE CAST IRON or someshit).

Not only that, but plastic will not ever rust; mine eventually will.

But I never got under my car and checked visually if it's even the same shape. It could be a different gas tank for the AWD or something.

Well, so you can look at it like that. Maybe you'll get a lighter more durable tank.

It's under pressure and it's flammable. Again, personally, I would bite the bullet and replace it if it's not crazy expensive.

 

[Bill Hincher]

the origin of vent for the gas tank starts at the charcoal canister, the problem was fuel would leak through the lines in the event that the car rolled over in an accident so the engineers had to place a one way /rollover valve in the line between the gas tank and the canister so fuel would not drain that direction, but the one way valve had to allow air into the tank as the fuel left the tank, so from what you are desribing , you will find a valve on top of the gas tank that is not working
the reason the valve will be mounted so far in the rear is because you wouldnt want the fuel to be near the engine compartment in a rollover accident , so the one way valve you are descibing is not the same as I am reffering to
the only other thing is that some vapor/vent lines ran up into the rear window posts next to the rear glass and if the car was in an accedient , the hose could be pinched/bad

 

[miguelmcv]

I don't know in a 1g, but on my 2g, It has the vent hose attached at the top of the Tank, which is difficult for fuel to get into the line.

Like (Bill Hincher) Said, The line has a one way valve, But In my car, it has only one valve, which is at the Canister.

If the system works good with out the valve, then,...,, your valve is not working correctly.

I would say Just, replace the Valve from the canister and you should be OK.

 

[Tfitch90]

Yea that shit was offensive. "Afro engineering" Kick your self in the nuts !

 

[obsidian]

Yea Boi. Go kick YOURSELF in the nuts. I've apologized already, no need for smack talk from you jack wagon.

 

[griffin81]

I think it might be easer to just remove the old gas tank. Then install a racing gas tank in the trunk that fix youre problem.

 

[obsidian]

I think it might be easer to just remove the old gas tank. Then install a racing gas tank in the trunk that fix youre problem.

Y'know I have thought about this but here is my dilemma.

1. Its a AWD so the trunk has that notch for the spare that sticks up and would make it more difficult to get a good tank in there.

2. My trunk is FULL of tools. Because DSM Race Car!

3. Fumes suck balls and I'd rather NOT have to deal with that.

4. I love stock looking vehicles with MINOR exterior things to ass flavor. While the fuel cell wouldn't be visible it would still annoy me for all the extra stuff I had to do and the unstockness of it.

But! To all of those who actually do have a fuel cell, could you post up pics? I'll tease this idea for a bit.

 

[3kgt2nv]

im doing a fuel cell on a 90 right now and unless your racing the car keep it stock and fix the issues. its not just about ease of use a fuel cell is no where near as strong in the case of a rear end collision.

 

[obsidian]

I guess I never marked this as solved.

here is my fix.

It turns out it was the little blue canister. That is what appears to be a relief check valve for the fuel tank. Lets venting fumes out but nothing in. It was stuck closed so the air pressure couldn't go past it and vent. Instead it vented through the fill neck.

My fix?

I removed the blue canister and filled it with wd40. I then used a small tool to go inside of it to actuate the rubber seal on the inside physically. I did this multiple times all around the seal and then dumped the wd40. I refilled and did the actuating multiple times until I was comfortable enough.

I then used my mouth to blow on the side towards the arrow. If the 2psi my lungs create can actuate it, and it did, then it works.

Reinstalled and never had a problem since.