Fuel smell from my 1998 Roe GTS

[viperpaul]

Hi All,
I am hoping someone here can help guide me...

I bought a Roe GTS last year and have always noticed the fuel seems to be evaporating and smelling the garage out. I have had the car parked up for the winter with no fuel in it and therefore no smell (as it just seems to disappear, parked it with a only gallon or two in it). No marks on the garage concrete floor.

I have put in 3 gallons today to the empty fuel tank via cans and was very careful not to spill any. I went back into the garage an hour later or so and sure enough the fuel smell is back. I have not switched it on so no electric pump has been used to move the fuel up the lines to front of engine at least not with any pressure other than gravity.

It has a huge 1000HP+ Weldon fuel pump and race fuel filter behind the battery. I can see or feel no leaks on any connections to these. I have removed the wheel arch liner by the fuel filler neck and tank to inspect tank and pipes but can see no leaks. All fuel lines are braided and the fuel hose has rubbed up against the battery and got discoloured black and slightly frayed but feels perfectly dry (I had wrapped toilet roll round the black area of the hose where it looked like the leak may have been but it remained dry last time I fired it up. I was hoping that was it). It cant be injectors or at the front as no pressure has been used since the fuel was put in, right? I have never had more than about 1/3 of a full tank with this car and it stinks even if there is only a gallon in it so not overflowing the fill hose that I know can crack on the side of the tank. That looked fine. I think the smell seems worse in the rear bumper by the fuel pump and battery but hard to pinpoint, smells both sides really but back end more but no fuel leaking that I can find. It seems to lose fuel when parked up so I'm confused where it is going!! If it was losing a gallon a week surely I would see it somewhere as a residue, could it lose this much by evaporation? (I am still not sure if I'm imagining the fuel loss at this rate) I left the lid off a gallon can and it did not seem to move level in the week that I tried.

The fuel filer cap does not seem the source and closes with a decent spring action.

Thanks for reading my ramble!

Any help on diagnosis would be greatly appreciated!

Paul

 

[ViperJeff]

Guessing-non expert

The seal on the gas tank, probably damaged during mods to supply propper pressure in the fuel system

 

[viperpaul]

Thanks for the help. Are you referring to the seal at the top of the tank for the sender Jeff?

I am also a little confused as not only does it smell it seems to lose a gallon or so every week or two when sitting in the garage (though I may be imagining this much but the level drops)
Am I right in guessing that the fuel is pumped through the top of the tank via a combined pump/sender unit (this seal area) or does it have a connection to the bottom of the tank? A leak in that top seal could cause a big smell but doubt it could cause me to lose much fuel when standing for a while really, what do you think?

And yes I'm not an expert lol.
Is there another way to do the seal without the 6956 Tool? A cheaper alternative maybe?

 

[ViperJeff]

Yes....

I had this happen on a old truck I have. We changed out the pump and about 2 months later we had that smell, all the time. We screwed up the seal. Couldn't answer the evaporation question, damn thing gets horrible mileage, so it's always been bad

Good luck

 

[viperpaul]

I will take a look at that over the weekend Jeff as I think it may well be there. If no electric fuel pumps have been switched on and its smelling as soon as I put fuel in it I guess it must be tank related as if fed via pump in tank then nothing would have come down the fuel lines. I have inspected the breather pipe and hose to tank connection and found no leaks there just dry dirt/dust.

I have owned it for just over a year and not driven it yet as I had to do the head gaskets due to a leak from the expansion plastic bottle in front bumper combined with a slight leak from the Fluidyne radiator causing an airlock. It is meant to have over 700 RWHP and 1000 rwhp when running the Nos system I have counted over $35,000 in parts alone so I hope when I have sorted the Fuel smell it and summer arrives it will be a fun ride, and much faster than my Corvette.

I have never had American cars before, Ferraris, Porsches, TVRs, Maseratis, Subarus and Evos, BMW Ms etc but I have to say I love the pureness and uncomplicated nature of these cars not to mention there presence and drama. Im a convert. I think in Europe the feeling is that they are all overweight and no good around corners but that is rubbish, 1g and not much different to a VW Golf in weight is Amazing.

 

[steve e]

There is a special tool to remove the fuel pump. And its easy to screw up the seal. If you are in the US there is at least 10% ethanol and evaporates very fast.

 

[viperpaul]

Cheers Steve, well I removed the panel above the tank and it all looks and smells ok.

Its has no fuel hoses actually coming out the top just 2 breathers one small and one large and one electrical plug. There is another blocked off/plugged larger hole where the original pump must have been maybe??? I thought it should not have a pump in the tank if I had this huge pump in the rear bumper.

So it looks like the feed for the fuel pump must come from the bottom of the Fuel Tank. Is this a know situation/mod? There is no leak at this Braided hose joint at the bottom of the fuel tank whatsoever.

Any other ideas to check?

Thanks