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Al
Join Date: Apr 2011
Location: SO CAL...Huntington Beach and Rancho Cucamonga
Posts: 5,207
Re: '69 Fuel Vapors in Garage
Go to home depot, the lawn mower parts section. Get a lawn mower air filter, the one made of foam. Cut a piece of that and insert it into the end of the fuel vapor/liquid separator. You want to mount the separator as high as possible with the 2 fitting ports pointed down.. An additional hose can be installed from the separator top and extended as high as possible the looped down to prevent fuel from leaking onto your car. Some have taken this hose and dumped it at the end of the frame near the bumper. An additional small piece of the foam can be inserted in the end to keep the bugs out.
A common issue with the 69 vent system is fuel leakage from the vent if stored on an incline or with a full tank of fuel. Resisting the urge to top off the tank helps, but fuel surge can also cause leakage out of the vents. That's the purpose of the extended tube to the bumper, to keep that fuel away from the car and hot exhaust.
You should have a non vented fuel cap on that car.
An enclosed air filter will help to keep fumes in as compared to an open element.
You should check all your fuel lines for leaks since you've had the car for a while and the fumes seem to be getting worse. Sometimes there will be a build up of dirt or oily substance on the hose at leak points. Trace and check all fuel lines and connections.
Might look into adding vents to exhaust fumes out of the garage. Maybe some of your vents are blocked if you have any. The garage should be properly vented to keep the fumes out of the garage. The fumes are heavier than air so will tend to concentrate near the floor.
You can install a later model, like 71 or 72 EEC system, but your 1 vent short on your tank and I'm not sure you could tee into one of the current vents and get the system to function correctly. I'm also not sure that this system would eliminate fumes from the carb area.
I haven't seen that pressure valve Bruce describes, but it would have to allow flow in and out of the tank to function properly as a vent.