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Today's Question - Gas Tank

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JPSmit

JPSmit

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I have already purchased a new gas tank for the car. BTW, my wife & daughter have named her Miss Triss. Anyway, I was going to throw away the old tank BUT it has a vent/ breather fitting and the new tank does not. I have no plans to reinstall the old pollution stuff. Any ideas what to do? TIA JP
 
Punch a tiny hole in the underside of your gas cap so it vents through the cap
 
Venting your tank to open air is throwing away fuel. Granted, it's a small amount of fuel, but enough to give a lab rat lung cancer and rob you of about 1-2 mpg in the summer.

You could drill a hole in your fill pipe, GOOP in a copper or aluminum tube (whatever you have lying around) and use that to hook into your car's existing ELC system.

BTW, the ELC system robs nothing from the performance of your car and can be easily "rebuilt" for about $10. All you need is aquarium filter charcoal and a couple of coffee filters. Check out https://shadetreemg.com/cannister.htm

Okay, sorry everyone. I am done with my sermon.
 
[ QUOTE ]
Venting your tank to open air is throwing away fuel. Granted, it's a small amount of fuel, but enough to give a lab rat lung cancer and rob you of about 1-2 mpg in the summer.

[/ QUOTE ]

Are you serious with that statement, Morris?

Think about it - 1/8" hole in bottom of gas cap vents only built up pressure from tank...when there's no pressure, the cap's sealed...when there's pressure, it vents through the 1/8" hole....no gas - just pressure.
 
Some minor amount of fuel vapor would escape, but it would likely be negligible.
 
Pressure = vapor = fuel

Gasoline releases more vapor when agitated (ie. driving conditions) as well as when heated (ie. Florida in the summer).

Therefore, there would be few conditions in which JP's car would not be releasing vapor.

I estimate a well tuned 1500 Midget should make about 27mpg average. Losing 1 mpg is only .037 gallons.

Negligable, I agree, but if your car is already equipped with everything you need to recover that vapor, why not do it?

Just my opinion...
 
Morris wrote:
[ QUOTE ]
...Negligable, I agree, but if your car is already equipped with everything you need to recover that vapor, why not do it?

Just my opinion...


[/ QUOTE ]

And valued it is. No argie about recovery if the ELC & "gear" is in place. My impression was it was half missing, and no intent to reconfigure it.

And yup, Florida sun is a kick-butt way to evaporate just about any fluid... especially if it's as volitile as gasoline. I think even hypoid gear oil would disappear from an open container 'round here... I know BEER does /ubbthreads/images/graemlins/wink.gif
 
Oh...ummm... that was me that drank all your beer.

sorry.
 
Skews th' curve on my Evap Loss Experiment into th' weeds...

Stop THAT!
 
And to further widen the field: the same as the pre-68 MGB's.
 
My 1500's gotten 35 mpg! /ubbthreads/images/graemlins/smile.gif (with fully modded engine and dual weber 40's). Of course, that assumes I don't drive like a crazy person!
 
Thanks for all the opinions. I recall a friend some 25 years ago who had a VW Rabbit. The charcoal filter got clogged and the fuel pump literally sucked the fuel tank into itself. Remarkable! Couldn't happen with a carb I think but still...
 
Nope. The Rabbit was a CIS system with a fuel pump capable of suckin' a golfball thru a garden hose. Ain't a Lucas pump built wot'll do that. /ubbthreads/images/graemlins/grin.gif
 
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