Third fuel line?

SummerSledSix · 03-17-2002, 10:53 AM

When I had the car apart last winter, I replaced the plastic fuel lines with flexible metal tubing, cranked up the diameter of the supply line for the presumably thirstier six. When I was yanking the old plastic stuff, there was a third very skinny tube that I believe went from the plastic tank on top of the fuel tank back to the engine air filter(?) (this is on a '76). I decided it wasn't important and did not replace it

.

Now, of course, is a fine time to ask, but what was this sucker for, and where did it really go from/to? I assumed it was some rudimentary environmental plumbing, and since my car is past the 25 yr old threshold of environmental pain here in CT, I ignored it. Am getting the occasional whiff of gas fumes, my connections are dry, figure this "missing link" might be the culprit. If I restore it, where might I hook it up to my 3.2, any opinions?

Kevin Powers · 03-17-2002, 12:17 PM

the hose went from the expansion chamber on top of the fuel tank to the charcoal filter canister which allowed fumes to be drawn back to the air filter( just like you thought). there was a second line that ran from the fan shroud back to the c.f.c., sort of a recirculating pump that was engine driven. the hoses run under the left rocker panel.if the metal tube on the e.c. is open that could account for the fuel stink esp. after a fillup and a hard right corner. the haynes man. diagrams the system pretty well on pg.58. there should be some manner for you to hook this up.

SummerSledSix · 03-17-2002, 02:17 PM

Thanks, Kevin. Didn't expect Haynes to be of any help here, didn't even bother to look (duh). My car used to have an EGR/CAT system, but it and the charcoal canister if there ever was one, is long gone.

I was thinking of hooking a hose to the expansion tank vent (#6 in that diagram) and just running it back to the air cleaner on the six. That would theoretically suck any fumes into the engine where they might actually do some good. Think I'll also read what Mr. Haynes has to say on the fuel system in general.

Kevin Powers · 02:51 PM

john, after reading your post and thinking about my reply i've come to the conclusion that it might be in my best interest to reattach the recirculating system in my car, even though i've converted to carbs. the elimination of explosive fumes and the environmental issue as well. if it something you want to do maybe you could switch to an earlier model fuel tank w/the c.f.c. something else on my list of things to do, like i don't have enough at this point. good time to have the tank cleaned so it's good for another 30 years.

line #7 could be crutial too,hooking the tank up to a potential siphon, line#8' might upset the jetting

Dave at Pelican Parts · Dave at Pelican Parts's Garage

70-74 cars had the cannister up front by the fuel tank. There were lines running from the fan shroud to the cannister, and from the cannister to the air cleaner, through the left-side rocker panel.

74-76 cars (yes, 74s had some of each) put the cannister in the engine bay. There was one thin line going from the expansion tank on top of the fuel tank back to the charcoal cannsiter. That line ran through the center tunnel, as described.

--DD