battery to trunk - risk of gas fumes/electrical combo

[Happy Face]

I've picked up one of the rear braces/battery mounts for the trunk. Its something I really want to do for all the right reasons. However, I am hesitating because when I open my trunk, I smell gas. Its not overwhelming, but it is there. My wife says that when she gets in the car she smells gas, I may have gotten used to it by now.

Anyway, first I am wondering if indeed there is risk by putting a battery in the immediate vicinity of the gas tank, and in gas fumes (explosion comes to mind).

Second, if the fumes are unsafe, what can I do to fix this?

by the way, its stunningly beautiful here in south texas today!

dave

[jasonix]

The battery itself actually produces flammable gasses... the only risk you will encounter is if you have an arcing connection from a battery clamp, cable short or faulty wire connection.

-Make sure you attach the clamps properly by spreading the clamp open enough to slide the clamp to the bottom of the post. Also be certain the clamp tightens securely before closing completely.

-Shield the battery cable by using grommets anywhere it passes through holes in the body, and make sure the cable is secured against other surfaces to prevent rubbing and relative movement.

Nonetheless, a raw fuel smell should be fixed... most of the following connections are in the trunk...

[Guest Anonymous]

I had the same problem and it turned out I had a cracked filler tube. I just replaced it and the smell has gone away.

[Happy Face]

Inspection of the gas tank reveals the following:

We had a recent rain and some of the wetness in the trunk could be from water leaks, but the gas smell is unmistakable. I'm wondering if I need to remove the entire tank, or if this is normal given the proximity to ten gallons of gasoline. No question though, that filler hose needs to be replaced. Where to I get this stuff?

cheers

[Marty]

Someone here should have a good filler neck. You rubber gas lines look like there the same ones that your car left the factory with 34 years ago. I would replace all of them and cap the fuel return line at the tank if its not in use. I also would run the tank vent out through the trunk floor. If you still smell gas then the tank will probably need to be sealed.

[cj]

Don't forget, BMW fuel lines are metric. Your local BMW store will have the proper diameters and type of hose for the vapor/return lines. They're cheap and have BMW printed on them.

Cris

[KFunk]

As for it being an unsafe combination, it is the factory arrangement in some safe cars.

Mazda miatas have their battery in the trunk from the factory, which is also the same location for the gas tank and filler neck that are fairly exposed. But miatas use a special battery to avoid the spilalage of battery acid in the trunk, and producing the gases of a normal battery. Some people call it a gel-cell, but its really an abosrbent glass mat (just tightly packed so essentially not much liquid). For the little bit of gas that is produced, they have a tube to route it out of the trunk and vent to the air. But recently most people think thats not necessary, and they just seal the battery completely, and the gas produced is so insignificant it doesn't matter.

You can't buy an AGM/miata battery anywhere though. Even the mazda dealership won't sell them, yet they arrive in new miatas. To get one, you have to get a WestCo brand (www.westcobattery.com i think) for like 80 bucks.

I have no idea if the WestCo is suitable for a 2002s purposes, though. But if its got enough cranking amps to start it, I'd try it. You just have to be careful about charging them quickly, like if you run the battery down by leaving on the headlights and then jumpstart it. The rapid charging of the alt can fry it. You can still jumpstart it, but just drive it enough to get you home and trickle charge it overnight.

Oh, and the other benefit of the miata battery is that I think its lighter and smaller.

As for the risk of electrical mishaps, you could probably put it in a regular plastic battery box and cover the terminals properly, and you'll be fine. My miata doesn't have a battery box though, its just sitting there in a bracket.