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Discussion Starter #1
I had pretty much filled up my 2001 before winter, but I did it just with gas cans. I took it for it's first drive this year, and after about 4 miles I started smelling gas. I went back home and hoped it was the vent hose. I looked around the car and there was some fuel leakage from the filler cap that was smeared over the rear body.

Now I didn't try to really get it full in the winter, but maybe I got unlucky. I would expect that filling up at a station would be about the same though. Later I siphoned about 4 gallons out and took it for a drive and it seemed OK. So I'm wondering what happened here. I'd guess that the tank pressurized and vented some of the fuel, and maybe the vent hoses in the car leaked a bit at the same time. Could that be an issue with just too much fuel? Is it a bad idea to really fill these cars up? Or is there something else I should be worried about?

Thanks
 

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If you were full, could be caused by loose or leaky cap, as everything warms up and expands as you drive. If you were not full would look for a clogged vent hose including the charcoal canister(I assume the V8 has one)
 

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Not really a problem filling car up, but no good reason to top it off and leave fuel in filler neck. The vent hoses can leak, but not out the cap. Because there are two tanks the fuel will flow from side to side if there is a reason to such as a tilted roadway or sustained curves.
 

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FWIW at one point my '88 would leak gas out of the cap when I was driving at highway speeds with a tank more than 3/4 full.

I came to the realization that airflow over the car must have been sucking the gasoline out.

I replaced the caps (my '88 has two) with new factory caps; that took care of the problem on one side but not the other.

Finally, I bought one of those butt-ugly, spring-loaded metal caps from an auto-parts store, and that fixed the problem forever after. (Good thing there are covers on the gas fillers!) Ugh. :huh:

I'm sure your cap is different from mine, though. Around 1990 Lotus went to a GM style screw-in cap instead of the quarter-twist type of the early Stevens cars. But the point is, a loose fitting cap CAN result in gas being sucked out of the filler.


+++++++++++++

On a 2001, I wonder why you didn't get an evap code/check engine light, though. The OBDII system monitors that stuff.
 

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Discussion Starter #5
My potentially incorrect assumptions are that the gas cap is setup to vent pressure if the pressure gets too high. A friend with a racecar did something with his charcoal canister (I think incorrectly) and that was causing his tank pressure to rise to the point where it was venting from the cap. My impression was that was as designed, so that the pressure is vented controllably instead of blowing a hose off somewhere else, but I could be making that up.

Even if that is true though, the question would be why the pressure is getting that high. I don't think the cap was loose, but I guess it could be defective somehow. The whole charcoal canister setup is something I've never understood or had to look into, but I guess it could be related to this.

But normally if you fill up, doesn't the pump shutoff when the fuel pretty much reaches the nozzle. I don't THINK I had anymore gas in it than that anyway.
 

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I believe on cars for many years now venting of excess pressure is to go throught the charcaol canister. The charcoal absorbs the gasoline vapors as a pollution control device. The engine then sucks the gasoline back into the intake via a vacuum hose and a purge solenoid. The fresh air intake for the vent system is also on the canister. No gas or vapors should be coming out the cap.
A highly pressurized fuel system is a potential disaster especially on the mid engine Esprit.
As a rule with the Esprit dual fuel tank setup, if you fill till the clicker on the pump activates, and then don't put in anymore gas ie don't top off then you shouldn't be overful as it takes the fuel a few seconds to equalize with the other tank..
Again check your cap and don't top off. If you are still leasking after that you have a problem and a fire hazard.

Randy
 

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[snip]
As a rule with the Esprit dual fuel tank setup, if you fill till the clicker on the pump activates, and then don't put in anymore gas ie don't top off then you shouldn't be overful as it takes the fuel a few seconds to equalize with the other tank..
Again check your cap and don't top off. [snip]
Yeow! - I've been removing both caps and filling up and 'topping off' rather heavily. :panic:

Been doing it for 6 months/7100 miles with no problem (yet):eek:.

However, sounds like good advice for the summer- THANKS!

Removing the 2nd cap 'seems' to allow the car to fill up faster.

The lame nozzle angle (as documented in the driver hand book) forces me to hold the nozzle 100% of the time in the horizontal position. If anyone knows the bizarre story behind that design 'detail', I'd like to hear it.:huh:
 

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Yeow! - I've been removing both caps and filling up and 'topping off' rather heavily. :panic:

You can do that with the '88. :clap:


Since '98-99, the US Govm't has mandated vapor-capture systems on all fuel fillers (which was why Lotus "disabled" the RH filler on newer V8s). There are purge pumps and valves that you really don't want to damage by over-filling.
 

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On the V-8's Lotus went to only one gas cap on the left side. If you do not fully click the cap it will leak. If the gasket is missing it will leak. If you bend the neck with the filler nozzle it will leak. If it leaks you will eventually set a code on the evap system. The cap does not vent. The system is meant to pressurize a little. It sounds to me you just have a cap that is not sealing. Be sure to make it click when you put it on. Maybe you wound up with the wrong one. Modern cars now tether them so you can't lose it or mix it up with other cars at the gas pump. Happens a lot. You are on one side and put your cap on top of the pump. Someone on the other side does the same thing. One of you grabs the wrong cap and screws it on. Also common with mixing up credit cards. ALWAYS check your card before you pout it back into your wallet!
David Teitelbaum
 

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Don't know about the V8 cap, but on the 4s most other caps won't fit/won't be able to close the flap as the Esprit requires a low profile cap.
Agree that the cap needs to seal well. Also due to the angle of the filler pipe, gas will splash up the pipe under acceleration if the tank is too full.
 

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Discussion Starter #12
Thanks guys. I guess I'll need to pay more attention. I don't think I left it loose, but I can't swear to it. I might have overfilled, but that would have been bad luck. Is there any way to check if the gas cap is broken or an incorrect cap? Besides waiting for it to leak again? Is it cheap to just get another cap?

I would just keep the tank less than 3/4 full, but the gas gauge is pretty unreliable so I'm afraid I'll get caught out at some point by trying to do that.
 

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I think caps are about $25 from JAE. it is a common thread Toyota/Honda, but it needs to be low profile.

The best way to check is fill up your car when the engine is hot, pull away from the pump and go look at the caps and listen, look, smell. The gas in the tanks will expand and leak out a leaky cap.
 
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