Fuel Smell in Garage?
- Thread starter fsts2k
- Start date
For those of our readers that don't have an SPF GT40 this is what the bottom of the locking gas caps looks like with the rubber seal removed. As you can see I just bypassed the maze by drilling a vent path thus bypassing the whole maze issue. I of course lost one of my caps and I'm now using non locking type which I'm not sure how they are vented.
I've had a gas smell in the car since the the first day I put gas in it.
I've had a gas smell in the car since the the first day I put gas in it.
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Seymour Snerd
Lifetime Supporter
I wish I understood that....
One explanation is that there's less trapped air to expand and force fuel out so less comes out.
Or that there is a fuel level above which there is not enough trapped air to force any fuel out. And of course this is true in that to force fuel out the expanding air first has to fill the filler neck all the way up to the cap. So if it expands less than that, nothing bad happens.
Another is that there is no trapped air but because the tank is more full there is a lower volume of fumes to "evaporate". However, I would expect the evaporation rate to be a function of the area of fuel surface in tank, which is pretty much independent of the fuel level (the area actually rises as you fill the tank except for the last 1/2" or so).
Tim Kay
Lifetime Supporter
I find it to be the opposite in my garage, when I have half tanks or less it smells less, in fact almost no smell at all :shrug: When full, let's just say it's bad enough to warrant fire extinguishers.
On another note, I wonder how effective the roll over breathers work for expanding fuel. Common sense tells me they only work with a surge and not with a gradual raise in fuel level due to expansion. Nice to know I may be wrong.
On another note, I wonder how effective the roll over breathers work for expanding fuel. Common sense tells me they only work with a surge and not with a gradual raise in fuel level due to expansion. Nice to know I may be wrong.
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I am really surprised that this thread has such long legs. My SPF is #2117 which is a relatively low number. I have NEVER had issues with fuel surging, fuel smell in cockpit or garage, and my gas caps lock just fine, although I always leave them in the unlocked position so I'm not fumbling with keys when doing a fillup. My car is carbureted.
I also never had any crud in my fuel tank as some lower # owners have previously reported. I don't know, maybe my builder addressed these issues in the original build.
Mike
I also never had any crud in my fuel tank as some lower # owners have previously reported. I don't know, maybe my builder addressed these issues in the original build.
Mike
Seymour Snerd
Lifetime Supporter
re: Tim's opposite experience...well, that's why this thread has long legs... Actually it has them in part because I made it a mission to spend (waste) large amounts of time going after each and every complaint in my own build, and then to talk about all of it...
:shrug: is right!
The rollover valves that Bill Musarra used (Aero Tec Laboratories UK Race Car Division - 8mm In-Line Vent Valve Assembly with 50 mbar Pressure Relief, Vent Valves, TF-AF-009) have a venting threshold of 50 millibar (about 3/4 of a psi), so I assume they vent as soon as the pressure exceeds that, no matter how slowly it rises.
Seymour Snerd
Lifetime Supporter
Or, you lead a clean and sin-free life...
Actually there's a hint right in what you say: If the caps are not locked they don't seal (I think), which means you made your own vent in parallel with the marginal one in the cap. So that prevents you from having that particular failure mechanism (over-pressure from no venting at all).
I think a large part of the variable results is also they way the cars "live". For example, you would only get the expanding-air problem if you partially filled the tank, parked it so there was trapped air and warmed the fuel. That's three independent variables.
As another example,iIf your garage had air leaks and you lived in a breezy area, and mine were sealed tight as a drum, with identical cars I might have fuel smell complaints and you wouldn't.
Like Tim said::shrug:
I'll chime in as well as to not really having a problem with excess vapor. Only problem I had were a couple of loose hose clamps on some of the connections on the passenger side about a year into ownership. Pulled both filler systems, re-tightened all clamps, re-installed with no problem whatsoever since. And yes, I lock both caps, have no smell in the garage or cabin no matter what the given fuel capacity is, live in a hot climate and my garage stays closed 99% of the time.
I simply think it could be just a couple "Monday" cars that we're talking about here.
BTW, car is chassis 107, built in 07, and currently has over 6K miles on the odometer
.02
Rich.
I simply think it could be just a couple "Monday" cars that we're talking about here.
BTW, car is chassis 107, built in 07, and currently has over 6K miles on the odometer
.02
Rich.
Jack Houpe
GT40s Supporter
All these cars come assembled just enough to get it to the installer, I don't think there is one of them that rolled out of the plant that is perfect. For the price of a roller I think they did an OK job. Its the installers job to tidy up things to make it road worthy. It took me a year or little longer to get it where I felt comfortable taking it on long journeys, I now have almost 9000 miles on the car and its not left me on the side of the road but one time and that was a high pressure fuel pump failure that had nothing to do with SPF. If your running EFI you'll have to have vented tanks or a charcoal canister and lots of plumbing.
My wife complained about my CAV giving fuel smell in our attached garage. To keep peace in the family I made an easy fix!!!! I stored the CAV in a storage unit about one mile down the road from my house.
Problem solved except I couldn't sleep in my garage and caress it all night and stand and stare at it all day. I think these cars are more attractive then a young beautiful woman.
Good luck,
JOSEPH
Problem solved except I couldn't sleep in my garage and caress it all night and stand and stare at it all day. I think these cars are more attractive then a young beautiful woman.
Good luck,
JOSEPH
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Dimi Terleckyj
Lifetime Supporter
The great thing about a 40 is that it will keep it's curves longer than any beautiful woman and will never have a headache or not be in the mood.
Dimi
Seymour Snerd
Lifetime Supporter
Dimi, she's right there. She can hear you!
I beg to differ... Search on this forum and you will find enough 40's that have not been in the mood. The difference is that the 40 doesn't say "no" or "I am tired", it simply gives unmistakable clues such as:
- loud metallic noises
- no noises
- incontinence
- smoke from areas other than the exhaust
- steam
- etc.
That is because a lot of owners haven't figured out that you have to treat a 40 like a BEAUTIFUL WOMAN. You have to spend a lot of $$$$ on both to get them to give in to your wishes.
JOSEPH
Seymour Snerd
Lifetime Supporter
I just found another reason why one car might have this problem and not the others. P2160 has two tiny leaks. The first is where the welder of the tank assembly missed a spot in joining the rear face of the tank to the main body. The other is in one of the spot welds for the internal baffles. So I guess the tank was not pressure tested even though it has about six feet of welding on it all of which has to be air-tight. The tanks have the builder's initials and the date written in black. Hey, HJP, how's it goin'? You forget anything when you built my tanks on March 20, 2007?
Anyway, this might sound like something really difficult to fix, but tank removal actually isn't that hard; it's just a lot of steps. Here they are:
- Have a fire extinguisher nearby! Open the garage door! Drain the tank!
- Jack up the rear of the car to get the remaining fuel to collect at the front.
- Open the rear cavity and disconnect the crossover, feed and return (if any) lines to the tank. Cap these fittings (two 8AN, one 12AN). Or the right size neoprene plugs if you're careful. 12AN = #1 plug.
- Remove the two socket head screws holding the tank bracket to the frame.
- Remove the access plate on the door threshold (whole bunch of screws) and removed the fuel sender (5 screws). Don't need to disconnect wires, just set it aside.
- Jack up front just enough to remove the front wheel, and do so.
- Remove the access plate at the front of the sponson (whole bunch of sheet metal screws).
- Remove the two socket head screws holding the tank bracket to the frame.
- Disconnect two clamped vent hoses from front of tank.
- Disconnect fuel filler from top of body (six or so screws, a couple thick cork gaskets)
- Unclamp and loosen fuel filler hose from neck on tank and pull entire fuel filler assembly up from the top allowing the hose to come off the tank's neck. The tank is now free to slide out of the sponson. However, the front upright and brake are in the way, so you need to move them temporarily.
- Detach upper ball joint from upright by removing large hex socket screw at the top, holding nut underneath with a short open end wrench. Be sure to catch washer underneath when nut comes off; otherwise it can fall into the upright.
Loosen nut at the top of lower ball joint a few turns with short open-end wrench. - Raise upright a little with a padded jack under the axle.
- Tap the lower A-arm until it and lower ball joint drop down from the upright.
- Remove nut so ball joint shaft can drop all the way out of upright. The upright, axle and brake assembly is now free and can be set aside (forward), being careful not to strain the still-connected brake line and tie-rod end.
- Unscrew the cap beneath the lower ball joint. It has a raised hex boss. It will be full of grease that you don’t want to contaminate so set it aside appropriately. This is a good time to drill and tap the center of that hex boss for a grease fitting.
- Tap the threaded end of the ball joint downward through the lower A-arm and set it aside as with the cap. Protect the grease-filled end of the lower A-arm from contamination and damage to the rubber boot. If the rubber boot is cracked now would be a good time to replace it.
- The fuel tank can now be slid forward out of the sponson while the upright assembly is held above the tank.
- I fixed my leaks with some carefully applied JB Weld.
- As with all British cars, assembly is purported to be the reverse of disassembly. In this case it actually is.
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Seymour Snerd
Lifetime Supporter
Minor correction: in step three a better term for "neoprene plug" is "rubber stopper."
Some thoughts on testing fuel tanks in situ:
Probably the easiest way to pressure test is to open the rear cavity and cap the rear three (or two for the RHS) fittings with AN caps or rubber stoppers, and also remove the front access plate so you can disconnect the front vent tubes and plug those spigots with rubber stoppers, and plug the tank filler neck with a #10 stopper with a hole in it. The latter step still requires you to remove the filler neck assembly but that's only 6-8 screws.
You can feed a tube into the hole in the #10 plug and blow into the tank as you would a balloon (don't inhale!). You will find that if your tube is small enough (~1/8" ID) it takes the compressed air several seconds to flow back out of the tank. That allows you to quickly remove the tube from your mouth and stop it with your finger, although you could also clamp the tube while holding the tank pressurised with your mouth.
Thus you can wait to see how long it takes for the pressurised tank to depressurise. If there are any leaks it won't take very long, although you have to keep in mind the pressure you are applying is very low and thus would might take a while to let a lungful of air out via a small leak.
It might speed things up to use a hand pump or a compressed air source (careful!) which will allow higher pressures. The higher pressure has the advantage of causing any leaking fuel to leak faster, which in the case of a really small leak is an advantage for detection. An even better setup would be to include a pressure gauge somewhere (one of the AN caps or stoppers, or maybe into a second hole in the big stopper?) so that you could watch for pressure drop.
By the way the use of rubber stoppers protects the tank from being over-pressurised. They will pop out at some reasonable pressure unless you really jam them in, and that's not necessary to get a good seal. This protection may startle you. I did this once with the tank out of the car and was impressed by how high the #10 stopper went.
Rubber stoppers are readily available on Amazon with no, one or two holes.
Some thoughts on testing fuel tanks in situ:
Probably the easiest way to pressure test is to open the rear cavity and cap the rear three (or two for the RHS) fittings with AN caps or rubber stoppers, and also remove the front access plate so you can disconnect the front vent tubes and plug those spigots with rubber stoppers, and plug the tank filler neck with a #10 stopper with a hole in it. The latter step still requires you to remove the filler neck assembly but that's only 6-8 screws.
You can feed a tube into the hole in the #10 plug and blow into the tank as you would a balloon (don't inhale!). You will find that if your tube is small enough (~1/8" ID) it takes the compressed air several seconds to flow back out of the tank. That allows you to quickly remove the tube from your mouth and stop it with your finger, although you could also clamp the tube while holding the tank pressurised with your mouth.
Thus you can wait to see how long it takes for the pressurised tank to depressurise. If there are any leaks it won't take very long, although you have to keep in mind the pressure you are applying is very low and thus would might take a while to let a lungful of air out via a small leak.
It might speed things up to use a hand pump or a compressed air source (careful!) which will allow higher pressures. The higher pressure has the advantage of causing any leaking fuel to leak faster, which in the case of a really small leak is an advantage for detection. An even better setup would be to include a pressure gauge somewhere (one of the AN caps or stoppers, or maybe into a second hole in the big stopper?) so that you could watch for pressure drop.
By the way the use of rubber stoppers protects the tank from being over-pressurised. They will pop out at some reasonable pressure unless you really jam them in, and that's not necessary to get a good seal. This protection may startle you. I did this once with the tank out of the car and was impressed by how high the #10 stopper went.
Rubber stoppers are readily available on Amazon with no, one or two holes.
Dimi Terleckyj
Lifetime Supporter
Alan
My ex-wife once told me that if I go to the World Freefall Skydiving Convention she would leave me.
That was back in 1996.
I went, she went and I haven't looked back since.
People that know me have learnt not to give me ultimatums unless they are prepared for the outcome.
Dimi.
