Need help with fuel tank issue

[LuxMag]

I have a 70 Bronco and it is equipped with EEC (emissions evap control). The tank is bad/rotted and needs to go. I’m thinking of just doing a non ECC tank and bypassing the EEC system since vehicle is exempt from smog control in my state. If I put in a tank without EEC or vent valve, will a vented fuel cap suffice to keep the tank sufficiently vented? If yes, what do I do with the open vent line leading to the EEC canister and the line going to the carb from the canister? Any and all instruction and insight welcome.

 

[spap]

I think you would still want to run the. Ent through a charcoal canister , if the truck is in a garage with a vented cap it will smell like gas all the time

 

[1970 Palmer]

I have a 70 Bronco and it is equipped with EEC (emissions evap control). The tank is bad/rotted and needs to go. I’m thinking of just doing a non ECC tank and bypassing the EEC system since vehicle is exempt from smog control in my state. If I put in a tank without EEC or vent valve, will a vented fuel cap suffice to keep the tank sufficiently vented? If yes, what do I do with the open vent line leading to the EEC canister and the line going to the carb from the canister? Any and all instruction and insight welcome.

Is this on a vehicle that needs to have a visual emission inspection each year for registration?

In California they inspect 1975 and later vehicles for all of the special added stuff (like Thermactor pumps, etc.). It's a governmental PITA, that made me seek out a 1974 or earlier "emission exempt" EB to rebuild. My 1970 Bronco was originally sold new in WA State with a minimum of compliance items added.

There's really nothing wrong with using the charcoal canister to vent the fuel system. But, that's just a small part of the emission system. I used the new reproduction plain painted steel vented gas caps from TBP and I barely can smell any gasoline fumes with my nose right at the cap.

 

[DirtDonk]

Hey LuxMag, welcome to classicbroncos!
I agree that keeping the evaporative emissions is a good thing. But plenty of people have gotten rid of it too. While some do not have a negative experience from doing so, many do. So keep that in mind.

I have a 70 Bronco and it is equipped with EEC (emissions evap control).

You might want to call it something else during some discussions, since in Ford parlance "EEC" stands for Electronic Engine Control after computers started appearing on trucks around '83 or so.

And '70 was the first year that the charcoal canister was used on Broncos. It was a running change and some '70 models don't have the canister, while others (most?) do.

The tank is bad/rotted and needs to go. I’m thinking of just doing a non ECC tank and bypassing the EEC system since vehicle is exempt from smog control in my state.

What is a non-evap tank? All the normal replacements have the vent fittings. Do you have a line on one that does not?

If I put in a tank without EEC or vent valve, will a vented fuel cap suffice to keep the tank sufficiently vented?

Yes, but you will have to vent it. Customizing the cap in other words.
A standard two-way vented cap from an earlier model will not fit your filler neck. They changed the reach on the arms so you could not bypass the emissions components easily.
Most people just drill a small hole through the cap as their "exhale" vent. The later caps are still vented, but it's only one-way for "inhaling" and letting the tank keep from building a vacuum.

If yes, what do I do with the open vent line leading to the EEC canister and the line going to the carb from the canister?

Just plug it. Or remove it completely. I do not recommend the latter however, just in case you regret the move and decide to go back to using the charcoal canister after all.
Plugging it just keeps debris, moisture and spiders and wasps out of the hoses and canister. Since there is no fuel in the canister (or should not be) you don't have any reason to cap it off, other than to keep junk out of it.

From '70 until '76 Ford used the low mount metal charcoal canister on the passenger frame rail AND a plastic condensing tank behind a metal panel at the driver's shoulder.
They are known for splitting a seam (especially in colder climates I think) but are easily patched up.
It's all part of the same system. And it's fairly easy to keep hooked up if you have at least one vent tube on your replacement tank.

Good luck whichever way you go.

Paul