Alfa Romeo Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
414 Posts
Discussion Starter #1
I raised this question in the Spider forum and didn't get the responses I hoped for, so maybe the fuel delivery forum will... deliver.
Photos and background are at this link: http://www.alfabb.com/bb/forums/spider-1966-up/49973-fuel-tank-plumbing-issues.html

Since I can't go back to original with the dellortos in place, my options seem to be:
1) Install a vapor recovery tank with the vapor going to somewhere on the air cleaner box, like where the breather from the cam cover comes in, and put in a one-way valve to let atmospheric pressure into the fuel tank, but not let fuel vapors out, or
2) Use a vented gas cap.

Either of these would be after a tank cleaning and sealing, removing the nonfunctional fuel return line, replacing any bad fuel lines, new sender unit gasket, re-attaching the overfill hose, etc. 1) seems the best shot at getting vapors out of the trunk, and closest to the original design but is it a dumb idea? Since the amount of vapor from the tank will vary, won't the air/fuel mixture never be correct since there will essentially be unmetered fuel added to the air? Any better ideas? How are factory carb systems set up to deal with fuel tank vapors?

Thanks, Roger
 

·
Super Moderator
Joined
·
11,429 Posts
Roger,
The easiest way is to add an overflow nipple to the filler neck (braze), then vent it with a neoprene hose through the trunk floor, ending under the car. Just like a old Giulia.
Worked then, will work now, don't you think? Gordon Raymond
 

·
Registered
Joined
·
414 Posts
Discussion Starter #3
Gordon,
Sounds good to me. And since there is already a place to attach the hose to the filler pipe, very easy to do. So that would be in combination with a non-vented gas cap and no one-way valve needed, right?
Roger
 

·
Super Moderator
Joined
·
11,429 Posts
Non vented cap, a gromit through the trunk floor (no fumes in the trunk) and the tube ending under the trunk in the air stream. No valves. A nice benefit is the little puddle of gas under the car if you overfill! (Oh yes, tube end AWAY from hot exhaust, please!) Worked fine on all the Giulietta's and Giulia's, should work the same for you!
:DGordon Raymond
 

·
Registered
Joined
·
414 Posts
Discussion Starter #5
Thanks Gordon, sounds like good advice. One more project figured out-- now to just do it!
 
1 - 5 of 5 Posts
Top