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Center connection goes to the metal fuel line leading to the fuel tank.
The large connection at bottom-right goes to the base of the carb at bottom, left.
You need a "T" in the line from the PCV valve to the carb. Connect the branch to another "T" near the canister. That "T" has one small and one medium connection. The small goes to the small connection at top-right of your picture. The medium goes goes to bottom-left in your picture.
The small connection at top-left goes to a "T" in the line that originally fed the EGR. That line runs between a thermostatic vacuum switch in the front of the intake manifold and the EGR. If that thermostatic vacuum switch had been removed just connect to manifold vacuum. This is the "fourth line" added at some point. It just stops vapor from being drawn into the carb until the engine is warmed.
Dr. Rebuild (look it up) sells a kit just for the EVAP system that includes every hose and fitting mentioned save the "T" in the vacuum line and hose leading to the EGR You also get a illustrated installation instructions.
Where is the line going from ported/timed vacuum on the carb to the canister? That signal turns the canister ON so that it can purge its contents. Without any signal, it will just collect fumes until it is saturated...then drip fuel out the bottom.
Did you use the separate purge valve, like this one for example, inline to the PCV Tee, with a ported vacuum signal line from the carb? http://amzn.to/2BjyZSB
Amazon even suggests pairing it with the canister you selected.
Where is the line going from ported/timed vacuum on the carb to the canister? That signal turns the canister ON so that it can purge its contents. Without any signal, it will just collect fumes until it is saturated...then drip fuel out the bottom.
Also the "T" in the PCV line is used to provide another control signal to the canister that stops vapors from the car fuel bowl whenever the engine is running.
The "T" at the PCV valve is just a way to combine the purged vapors from the canister and the crankcase. That combined 'stuff' is sent to the carb base so that it can be burned with the normal fuel/air charge.
The only signal to the canister is the line from the ported vacuum outlet on the carb to the "carb" connection on the canister. At idle, ported vacuum is at 0" Hg. Once the throttle is cracked open, the vacuum level rises quickly to the same level as manifold vacuum. That way, the excess gasses from the canister (and PCV valve) do not affect idle quality (throttle closed); but when the car is cruising, the ported vacuum signal turns ON the canister to "Purge" mode.
I know this is an old thread, but maybe someone can help me. I have a 72, and there is a pretty large tube that is on the bottom of the fuel vapor canister. Does anyone know if that is supposed to connect to something? I removed the canister for a restoration a couple of years ago, and did not label it. The top of the canister has three tubes that are labeled, so am pretty sure about those.
02-08-2018, 07:23 PM
