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What is this hole for? Driver front side of rear inner fender

SDBMtber

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May 20, 2018
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130
I imagine this is well known to most. Mine was already disassembled when I got it. What’s supposed to get installed here? Seems like a hole I probably should’ve welded up.

Thanks
 

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DirtDonk

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That is on '70 through '75 EB's for the first part of the evaporative emissions system.
A "condensing tank" was mounted behind a screw-on panel right there, and the oval shaped hole had a rubber grommet with either three (single tank vehicles) or four (dual tank vehicles) flexible plastic hoses running to it.

There was actually a great picture posted up just a few days ago that maybe someone can find and link here for you to see.

It's not a bad thing to have actually, as it's good for keeping the fumes in the tank and charcoal canister, rather than outside in the garage.

Paul
 
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SDBMtber

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May 20, 2018
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Thanks Paul, appreciate the info. I think I found the other thread you were talking about.

Looks like best thing to do is get one of the mustang canister setups and install in the engine bay. With that, this should be one more hole I can weld up!
 

DirtDonk

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Yes, definitely the "best practice" at this stage. Get rid of the intermediate canister that can leak fumes into the cab anyway (which is why any in-cab fuel was banned in '76 in the first place I think) and use the more modern, easier to mount, cleaner looking and easier to find new part anyway.

Paul
 

AZ73

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Original look
 

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SDBMtber

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Thanks for the pic of the original. I can see why they kept that around for (only) 5 years...
 

DirtDonk

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Yeah, me too. But it made sense for our vehicles to do it this way until the better way came around.
They needed a charcoal canister to meet evaporative emissions standards (which is a good thing), but the canisters they had at the time were mounted pretty low on the frame rail.
This worked fine 90% of the time, but they knew these rigs were going to be used for all sorts of work and play activities. Some of which might put them on a nose-down or side-hill attitude for extended periods. I know mine got there a lot!
In those cases liquid gasoline could work it's way up to the charcoal media and ruin the function of the canister and add more fumage to the air. And gas to the ground too. Not good either way.

So the higher mounted tank allowed for two things. If the tilt caused fuel to flow up the vent lines, it got caught up in that tank. If it even made it that high.
And it could take enough vapor when conditions were right and just let the liquid condensate flow right back into the main rear gas tank. Hence the two lines to the rear tank and one only to the front.

So it did at least serve a purpose. Glad they came out with the better idea later though.
Mine took longer than most back then, but eventually started to leak out of the seam at the top and every time I filled the tank the cabin would fill with gas fumes. Lovely...

Got the new style on my '68, and one going on to the '71 next.

Paul
 

Crush

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I wouldnt weld it up. Find a plug to fit it and then use the hole for wireing and so forth. Makes a good access hole
 
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