Possibly a Very Dumb Question (1 Viewer)

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aggiecruiser

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Jan 16, 2007
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Mansfield, TX, USA
Okay,

I have read extensively on MUD about fuel evaporative separators, and the charcoal canisters. But all these discussions have been with reference to carbuerated engines. I have a 1/79 FJ40 with a 350 conversion that I plan on upgrading with EFI.

Do I still need the separator, and the charcoal canister with fuel injection, or does it all go away? I recognize that I will have a need for a return line to the tank, and that all the fuel in the system will be running at a higher pressure, but I am still not sure I understand whether or not the charcoal canister will still be a requirement to eliminate vapor smells.

Furthermore, if the charcoal canister IS still needed, where will the output route to on a fuel injected system. For the standard carbuerated system, I have read that the fuel separator routes to the canister, and the canister routes to the carb. So how would this all work for fuel injection?

Be gentle, I am just learning the basics for all of this emissions stuff, and have quite a bit of research and learning to do before I take on this task later in the year...(maybe next year)

Thanks,
Chris
 
hi there i would check to see if you need to worry about emmisions being the age of the cruiser. i dont think you need the canister anymore at all but do check
 
The charcoal canister and other evaporative emissions control devices will not be needed with the TBI configuration on your V8.
 
Doesn't matter what type of fuel metering system is on the engine. The canister is there to provide a way for filtered make-up air to enter the tank, and vapor pressure to exit. It will still need a source of ported vacuum to operate completely as stock. But that is not a requirement. The canister can still dump to atmosphere through the purge hose if there is no ported vac to connect to.

Or just drill a hole in the top of the fill cap, like any 1960's era vehicle, and watch (& smell) the fuel piss out on left turns. :hillbilly:
 
The charcoal canister and other evaporative emissions control devices will not be needed with the TBI configuration on your V8.

Poser,

If it's not needed, what do you recommend in terms of venting the tank? Should I buy a vented fuel cap and call it good? Should I leave the fuel separator and have it vent to the rear of the vehicle? What is most commonly done with the V8 conversions that feature fuel injection?

Thanks,
Chris
 
I have just run a piece of fuel line from a vent connection on the tank to the firewall and used a fuel filter as a breather for the tank.

Carb/FI/V8/F/2F does not really matter.

:meh:
 
Another problem solved for me through the help of MUD! Thanks all.

This forum rocks!

-Chris
 
hi there i would check to see if you need to worry about emmisions being the age of the cruiser.

Not in Texas; a '79 does not have any emmissions testing at all, only a safety inspection. :clap:
 
what if I have mine blocked off....... will my truck explode into flames soon.... ;)

Unless your tank can't find air from somewhere to replace the space previously occupied by gasoline as it's consumed, the tank will go under a vacuum and in worse-case scenario, starve your engine for fuel. Leaks around the gas cap/other will prolly prevent this from happening in all reality. Poser's method provides a known, filtered source for this purpose.
 
Just make sure when you vent the tank, if in the front or back, there is a baffle around it, so when you stop or take off it doesn't send fuel out, best in the top, w/ baffle around it , like the old Valve covers on v-8's, also just for conversation new EFI's IE: Chevy SS Trailblazer w LS doesn't run a return, like was on 98-99 LS1's. ( I'm in the process of putting a LSX in a 69 Camaro, but I will admit, I'm running a return line, afraid of vapor lock in this wonderful Florida heat
 

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