fuel odor

[hey,littlecobra]

hey, there, folks.

I just got my ERA 291 a bit ago, and am noticing a strong fuel odor in the garage. It emanates into the house, and is bothersome! I'm keeping the exterior garage door cracked a bit, and it is helping. Any suggestions on source, and a remedy?

Have "fueled up" once, and didn't spill any. Going to have to put an exhaust vent exiting the garage, or something!

thanks,

Kristen

[REDSC400]

What I noticed back in 1968 when I had a FE in my Galaxie 500 as well as today with the FE in the ERA is that if you let the hot engine cool while inside the garage, the large quantity of gas in the typical double pumper carb, evaporates to some extent due to the heat of the engine.

What I learned back in the day was to let the car cool down outside and not in the garage. The vapors "gas out" outdoors and there is much less in the garage.

Here in the Northeast, our winter gas has huge percentages of Ethanol from November thru April. The Ethanol seems to be more volitile and gasses out or is somehow more noticable to the nose. I have noted, that since November when it is really cold here in CT that the gasiness of the ethanol petrol mixure is more noticable...

[hey,littlecobra]

thanks, Art. I will follow your suggestion and cool it down outside. When i first got it a few days ago, i didn't notice it as much. But now that i'm driving it every few days, it has gotten stronger. I'll leave it out in the drive a bit. Logical explanation.

thank you, so much!

kristen

[Pete Munroe]

When I first filled the tank in my ERA 289 FIA, #2027 the garage stank of gas.

Eventually it proved to be leaking fuel fittings related to installing an electric fuel pump in the left rear fender...the 37 degree flares all leaked...replaced every inch of line with Earls fittings and line and that was solved as to seeps, but the stink was sort of still there.

The 289 FIA gas tank vent on the early series cars has to be sealed, and, on mine, the gas cap was defective and had to be replaced... the gas caps rubber gasket had slipped/squeezed out of center when assembled at Stant or wherever...the fumes would just seep past it up into the filler neck...it does not seal very well against fumes, especially overnight.

All that is corrected, no smell in the garage, but when you lift the trunk there is a faint gas smell...I have left the tank compartment bulkhead off for a year to look for seepage...I can NOT find any stains or wet spots, but it still is aromatic.

Who knows where it comes from, but the garage is ok...no concern about fire or stinking up the laundry.

Pete




still there.

[hey,littlecobra]

thanks, Pete.

will look at that situation, too.

kristen

[charlieh]

I also have petrol odour in the trunk of my Shamrock Cobra, yet outside of the car it is not apparent even when sitting in a closed up garage. There is no sign of physical leakage so I have not investigated further at this time. But it did encourage me to buy a fire extinguisher which is no bad thing for any Cobra owner!

Charlie

[Pete Munroe]

Kristen,

If you have a mechanical fuel pump, look at the bottom of the unit...if it is shiny clean, it may be leaking.

For years my 67' 327" Corvette had a awfull fuel smell...could never find it.

Finally, I ended up under the car with the engine hot and running and the crimp that hold the lower housing on a GM style pump was seeping like crazy all 360 degrees.

It only leaked obviously when it was running...it would evaporate almost immediately after shutting off and I wouldn't notice it was/had just been wet.

The pump was very clean while the rest of the front of the engine was standard oily road film...anything clean is suspicious.

Replaced the pump, no problem since...that was 10 years ago.

On another note, I did not know ethanol was more volatile than gasoline, don't think it is. But the refiners can vary the "Reid Vapor Pressure", (rate of evaporation at a given temperature) of the gas stock to suit the time of year.

Summer, higher vapor pressure to avoid vapor locking due to heat, winter, lower vapor pressure to help starting and general runability on a cold engine.

The "Reid Vapor Pressure" is critical in fuel used in aviation, trying to use MoGas, car fuel, can lead to problems in some light planes as the tendency to vapor lock due to extreme changes in altitude.

Some of the a/c systems tolerate the vapor locking tendency, some not so good.

Fortunately, its not likely to get your Cobra 5000 feet straight up to see if you have a problem though.

Pete

[hey,littlecobra]

uh, scratch, head....

I will have someone "look" at the fuel pump while running to see if there is gas leaking. another good idea. i checked the hoses that run from the fuel-fill through the trunk, and thought one might be loose where it attaches at the filler, on the inside of the trunk. Will get flashlight in daylight and check out the clamp. This is very frustrating, as I'm not very knowledgable in this! Blue Baby will be in the dog house (almost literally) if this doesn't get solved soon!

I haven't driven it since Friday, and would have thought any evaporated gas odors would have dissipated by now. Keep thinking, boys!
kristen

[Pete Munroe]

Kristen,

Sorry for the rather "off-in-blue" diatribe on "Reid Vapor Pressure", but that relates to gas stink being worse at different time of the year due to the evaporation of the gasoline...it forms vapor that STINKS...and causes vapor lock in cars and other stuff.

THAT was an off shoot of REDSC400 thoughts on how the NorthEast area gasoline/ethanol mix seemed unusually aromtic in the fall winter months...I was thinking that could very well be true as at different times of the year the gas formula changes for emissions purposes...although it seems that at colder temps, the fuel would evaporate at the same rate as warm weather due to the refiners adjusting the fuel formula to compensate for lower temperature.

(any petro-chemical guys out there to comment on that...? would love to know the facts...)

Anyway, if you are not knowledgeable car/Cobra savy now, as you get into the car...you will be. Do not give it up to "paid experts"...many are not.

Get out the flashlight and start poking around, next thing you know, you will be familar with every fitting, clamp, connection on the car...gas, oil or water.

Look to see if the fuel filler neck is holding spilled fuel...I do not think there is a drain on that compartment, so if you spill fuel in there as the tank is filled, the residue will smell.

Check out the fuel pump YOURSELF...helps for the car to be on on a lift, but use a mirror and a light and jack...drive the car up on several staggered blocks ofwood, whatever...look for obvious weepage, or just something SO clean, it has to be getting a gasoline wash down every time you run the engine.

My guess is the lower half of the fuel pump is shiny clean as it is leaking between the upper and lower half.

Lots of luck.

Pete

[CowtownCobra]

I have the same problem. Its not because of a fuel leak, its because cobras have open vent gas tanks, unlike new passenger cars which have sealed airtight systems to keep gas from evaporating into the atmosphere. If you look closely at your car you will probably see a hose from the top of the tank running down, and its open on the end. The gas in your tank is slowly evaporating through that hose. At least thats what I found with mine.

Add to that all the crap they put into gas now days, MTBE, etc, here in North Texas we are getting the "winter formulation" right now, and gas just stinks.

Try putting some AvGas or racing fuel in it. At least it smells better.

[Chaplin]

Kristen-
Cowtown may be right, but here is something else to consider along the same lines. I don't think early ERAs had a screw on gas cap below the monza cap- (new ones do). If I'm correct, on yours you just simply pop the cap and there is your filler neck. If the rubber seal around the monza cap has deteriorated from age, you may be getting fumes coming right up from the tank. I think some people have stuck racquet balls or tennis balls in the end of their filler necks to "seal off" the tank, and then closed the monza cap with the ball underneath.

[hey,littlecobra]

well, ok. Went looking for a tennis ball, and stuck that in the cap/pipe. So far so good. Will have to find a "guardsman blue" tennis ball. Figured that was the easiest fix so far, so will try it first. Also went trinket shopping, and got a flashlight and mirror for looking. Wasn't brave enough to buy the ramps and lifts yet, they didn't look long enough (ramps) or tall enough (lifts), so will go to better shop for those.

I understand what you mean about the gas/chemical make up of the fuel. Sounds a bit complicated, but you explained it beautifully. Thank you, again, Pete!

The gas cap is a "flip up" kind, and it is a little loose. Not real loose by any means, but a little bit of give. If that's all it is, ok. Am going to check the hoses too, now, with the flashlight and mirror. I like a challenge. Have sent hubby and 4 kids off, so i can play with my toy for a while. Also, re- doing the garage!

thanks, again, guys, and keep thinking....

kristen

[Jim Holden]

Just don't check it with a match...

J

[hey,littlecobra]

hey, Jim

hadn't thought of that.... checking with a match...

actually, I've been hanging out in the garage all evening, (except for Pep Boys run), and the gas odor is all but gone. Tennis ball trick is working, so far. The true test will be in the morning, after being in closed garage all night. Won't crack the door...

Of course, I'm sure poking around with my new mirror, helped, too. And don't forget the flashlight! Still got to think about that guardman blue tennis ball. And gearing up for a look under the car. And the seasonal change of fuel additives. Too Much....

Would a new fuel tank gasket work, or stacking two, or just leave the tennis ball? hmmmmm something about the tennis ball is a little disconcerting, kinda like the idea of checking with a match!

well, took some more photos and will upload to my gallery in a bit. Keep thinking, guys. You're doing good....

kristen

[Chaplin]

Racquet balls are blue, not guardsman blue, but definetely blue.

[hey,littlecobra]

Yes, Chaplin, I know, and I know I have one here SOMEWHERE! Looked for one; the dogs like them for playing with and chewing on. hmmm. I'll keep looking....
k

[Junket]

Kristen I know this might might apply but if you have a gas water heater or something with a open flame in with the smell of gas it can be deadly.

Ken

[sexzsn8k]

Kristen, I have ERA #624 and have the new Monza cap with a regular gas cap inside. I suggest that you call Peter, or Bob at ERA and see if you can send your old Monza cap in to them and have it retro-fitted. They did it for me at no charge. Then you wouldn't have to color coordinate the tennis balls.

[klayfish]

Glad you guys brought this one up. My FFR makes my garage smell all the time. I've never found any gas leak. Part of me thought it was that I just let it cool down in the garage (with the garage door open). Maybe it's the open fuel system. I had even considered making some kind of vent system out of the garage to reduce the smell. Thanks for these suggestions. I'll look into them too, without a match!

Steve

[hey,littlecobra]

well, ok, again. never found the racquet-ball. Garage still smells, but i'm imagining it is less smelly. Will go check it out in a bit.

The idea of retro fitting the Monza cap is good. Guess I'd have to take the old one off.... How long would it take, and guess I shouldn't drive it with no gas cap??!!

I'll call ERA.

thankfully, there isn't an open flame source in the garage. The thought has occurred that the garage door could spark when going up or down, or my regular drive (Toyota) could ignite something. Guess i better check the insurance policy on:

me. toyota. cobra. house. lots of hmmmm going on here...

keep thinking.

kristen


p.s. I filled up the cobra for the first time on Friday with Exxon - 93 octane. The odor started strong on Saturday. Connection???

Change brand of gas? Are they all the same? Additive, thing, again??? just thinking out loud...

of course, the original idea a fuel pump leak is still lurking out there. hmmmmmm.... also seasonal additives.....