Fuel leak when over filling.

[SIMid]

I hear this is common for some owners?

I have to admitt I did overfill mine by a few clicks at the pump, making sure the tank was to the max as I had a long drive ahead of me yesterday.

[DMC5180]

I would not call it common. I do the MAX fill all the time. no leaks. I did have situation years ago when I had been doing some in the tank stuff and did not get the FP boot snapped down on the tank opening flange. It leaked when max filled. A rotted or cracked boot would do the same thing though if the cover was deteriorated. The vent hose and filler hose could also leak at the tank connections if the clamps were loose.

[SIMid]

I would not call it common. I do the MAX fill all the time. no leaks. I did have situation years ago when I had been doing some in the tank stuff and did not get the FP boot snapped down on the tank opening flange. It leaked when max filled. A rotted or cracked boot would do the same thing though if the cover was deteriorated. The vent hose and filler hose could also leak at the tank connections if the clamps were loose.

I'll have a look through the boot and see what's going on. My guess is that the rubber flange may have popped off. But then, I don't get any fuel smell in the garage. So possibly a hairline crack instead? She never leaked like this when I filled her to the max since I've had the car.

[David T]

It could also be the sending unit. The rubber gasket could be missing or mispositioned. Maybe the ring is loose. Or I have seen the OEM one leak at the rivets. Get the access covers off and start looking.
David Teitelbaum

[thirdmanj]

It could also be the sending unit. The rubber gasket could be missing or mispositioned. Maybe the ring is loose. Or I have seen the OEM one leak at the rivets. Get the access covers off and start looking.
David Teitelbaum

I'm with David on this. It's a real easy thing to check, and replace if need be. Mine had this issue shortly after I got back from overseas.

[Rich06]

I had the same problem after putting in my new fuel pump.My new fuel pump boot had a small crack where it fits over the hoses and I took it off and reinstalled it 3 times before I finally saw the crack.
-Rich

[SIMid]

Thanks for the advice. I'm going to check it out tonight after work. Hoping it's just something loose.

I guess in the meantime, not to fill it to the max till I address the problem.

[SIMid]

Ok, last night I've gotten access to the pump and had a snoop around.

http://tinypic.com/view.php?pic=dmfhpw&s=6

Hope the link works above.

Seems all good except the large metal clamp was slightly loose. The large rubber cap was not cracked or split.

I have read somewhere that if you fill the tank with the nozzel towards the front of the car, it will overfill. If you point the nozzle to the windscreen, it will not overflow. A myth or for real?

[stevedmc]

Was the rubber boot gummy? Ethanol loves to destroy those things. If its gummy replace it. Every vendor (to my knowledge) sells the same part for about $50. DMCMW is where I would by the thing from.

Also, there is a vapor line that runs from the fuel tank to the fuel filler neck (where you put gas in the car). This hose was cracked on my car and wasn't even connected to the filler neck. I used to have gas smells and after I replaced the hose with one from AutoZone, the odor went away.

[SIMid]

Was the rubber boot gummy? Ethanol loves to destroy those things. If its gummy replace it. Every vendor (to my knowledge) sells the same part for about $50. DMCMW is where I would by the thing from.

Also, there is a vapor line that runs from the fuel tank to the fuel filler neck (where you put gas in the car). This hose was cracked on my car and wasn't even connected to the filler neck. I used to have gas smells and after I replaced the hose with one from AutoZone, the odor went away.

Amazingly, the rubber boot was in fairly good condition. Not soft and gooey, still firm and relatively feeling brand new (just very dirty from road grim). I believe the fuel system was looked at by the PO, so it was all sorted out a few years ago (5 maybe?).

There's no petrol smell when the car is stored in the garage, but I'll take another look at that vapor line.

Thanks for the reply(s)! :)

[David T]

To properly check the fuel pump you should remove the cover boot and see if there is any fuel around the pump inside the boot. If there is, the cover boot will not stop fuel vapors from getting out. Loosen the large screw clamp and pull the cover boot out of the way so you can get a good look at the fuel pump and boot.
David Teitelbaum

[Mark D]

Did you pull the upper cover where the hoses run to the /fuel filler neck? I'm not sure what effect it would have on fuel leakage but If the vapor recovery hose is kinked off that would cause pressure buildup inside of your tank causing venting at the fuel pump boot or fuel sender port.

On my car the hose past the roll over valve was sandwiched between the fiberglass body and cover preventing vapors from exiting the tank back to the recovery canister. I'd get occasional fuel smell in the garage after going for a drive. As far as I could tell the hose was flattened out this way since the car was originally built.

http://dmctalk.org/attachment.php?attachmentid=13960&d=1349881592

[SIMid]

To properly check the fuel pump you should remove the cover boot and see if there is any fuel around the pump inside the boot. If there is, the cover boot will not stop fuel vapors from getting out. Loosen the large screw clamp and pull the cover boot out of the way so you can get a good look at the fuel pump and boot.
David Teitelbaum

Toby messaged me on FB last night and said the same thing. To remove the boot and check for fuel on top of the pump. Slide the boot along the 2 rubber hoses and carefully watch the 2 wires on the side. If there fuel, then the rubber gasket around the pump has probably failed causing the fuel to leak. I'll take another look over the weekend. But he has recommended to purchase the newly released fuel pump if I have to take the old one out anyway.


Did you pull the upper cover where the hoses run to the /fuel filler neck? I'm not sure what effect it would have on fuel leakage but If the vapor recovery hose is kinked off that would cause pressure buildup inside of your tank causing venting at the fuel pump boot or fuel sender port.

On my car the hose past the roll over valve was sandwiched between the fiberglass body and cover preventing vapors from exiting the tank back to the recovery canister. I'd get occasional fuel smell in the garage after going for a drive. As far as I could tell the hose was flattened out this way since the car was originally built.

http://dmctalk.org/attachment.php?attachmentid=13960&d=1349881592

Thanks for the pic!! Really helps to see what I need to look for! :) I dont get any fuel smells, so at least, thats a good sign.

[DMC5180]

Did you pull the upper cover where the hoses run to the /fuel filler neck? I'm not sure what effect it would have on fuel leakage but If the vapor recovery hose is kinked off that would cause pressure buildup inside of your tank causing venting at the fuel pump boot or fuel sender port.

On my car the hose past the roll over valve was sandwiched between the fiberglass body and cover preventing vapors from exiting the tank back to the recovery canister. I'd get occasional fuel smell in the garage after going for a drive. As far as I could tell the hose was flattened out this way since the car was originally built.

http://dmctalk.org/attachment.php?attachmentid=13960&d=1349881592


Nice Mouse nest you have there.

[Mark D]

:-) yeah that was one of several that I've cleaned up... I'm surprised nobody else noticed!

[ArthurCaverly]

I had the same fuel smell since I bought my car in July, and actually just fixed it today. The boot had just come loose, apparently after the last owner did the fuel system. I could see fuel residue around the boot, and it was a little wet since I just filled the tank. I put it all back together, and it still leaked, because the hose clamp will push the boot up if tightened too much. So I used a litttle less tourque on the clamp the next time, and it STILL leaked. It took a few more tries, but the final problem was that the wires were not staying in the grooves in the inner gasket. Once the wires were in the right spot, the leak went away. Also, my boot looked fine, and wasn't gummy or anything.

Arthur

[David T]

Do not try stopping fumes by using the cover boot. There is not supposed to be any fuel in the boot that holds the fuel pump. If there is fuel around the pump you must figure out why. The boot could be bad, loose, the fuel pump not in the right spot, a hole in the boot, whatever. That pump is supposed to be DRY! The cover boot is just supposed to keep dirt and water out, not fuel or fumes in. The clamp for the cover boot DOES also tighten the fuel pump boot to the tank so that must be kept tight.
David Teitelbaum