Frustrated - need help with vent/vacuum lines (1 Viewer)

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Mar 27, 2003
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Location
North Georgia, USA
Ok- here is situation: ‘78 fj40 w/‘75 2f

when putting in my new fuel tank, I tried to get all fancy with vacuum lines and charcoal canisters and when I drive above 40 the fj40 stalls out from fuel starvation. The only thing left for me to undo is the setup I tried for the tank venting. I read 1,000 different opinions and setups and I think I just created a giant vacuum circular reference that stopped fuel flow to my carb at higher speeds.


Original setup: Removed old poly tank that was leaking. It had a non-vented gas cap. It had the tank vent hose dump out fumes under cab. Ie open tube. Yes had vapor separator off tank. No check valve. Just a hose to dump vapors. The fj40 ran great but did smell of gas fumes


My New thought setup: CCOT metal tank. I put in the vapor check valve after separator. Ran the fuel vapor line to an after market 2-port charcoal canister (tank) inlet. The second outlet is the PURGE outlet. Where do I run this to? Can I just run it to one of the air intake nipples? My carb is connected to the distributor…(vacuum?) do I T it into that carb/distributor line?

Or…is it just easiest to return to the orig setup. Just dump fumes from a cut hose.

I live in Georgia…so I don’t need to worry about any emissions.

Thanks for the help
 
Okay, I just went and studied the lines under the hood on my '77- the charcoal canister has a third line at the underside which is open to atmosphere with a (I believe) check valve. The purge line runs from top of CC across the firewall in a hardline - then soft line to a VCV / (or) VSV ? mounted on inside of fender, then the line from that valve goes to the gas filter at the top and front side of the intake manifold.
HTH
 
Okay, I just went and studied the lines under the hood on my '77- the charcoal canister has a third line at the underside which is open to atmosphere with a (I believe) check valve. The purge line runs from top of CC across the firewall in a hardline - then soft line to a VCV / (or) VSV ? mounted on inside of fender, then the line from that valve goes to the gas filter at the top and front side of the intake manifold.
HTH
Thanks for checking
I don’t have the oem canister
I have an aftermarket ac Delco one that only has two ports. “Tank” & “purge”
 
Thanks for checking
I don’t have the oem canister
I have an aftermarket ac Delco one that only has two ports. “Tank” & “purge”
Yea, I saw that; perhaps you could 'add' a third vent at the bottom without a check valve- I do not believe the vacuumdraw is very strong.
 
Thanks for checking
I don’t have the oem canister
I have an aftermarket ac Delco one that only has two ports. “Tank” & “purge”


i offer the updated CHECK VALVE and one way in smog compliant gas cap oem also


please see links below

you absoluty need these 2 parts to keep things all safe and happy with your job scope long term on the oem fuel vapors system in general


thanks matt






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i offer the updated CHECK VALVE and one way in smog compliant gas cap oem also


please see links below

you absoluty need these 2 parts to keep things all safe and happy with your job scope long term on the oem fuel vapors system in general


thanks matt






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Thanks
I have all the parts and extras. Just trying to figure out best way to connect all.

I’m not interested in any smog regulations
 

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