[TR] TR6 gas tanks?

[Bud Rolofson]

Does anyone know what year TR6 had a gas tank with two vent pipes on the top of the tank. They both connected to a 4 sided connector with one of the out lines going out to the carbon canister and the second out line out to the filler neck.
I just discovered one of the vent lines right on top of the tank where it couldn’t be seen was not connected to the four way connector and was the cause of gas fumes in my shop, and probably a reason the gas mileage had dropped.

I’m thinking about capping one vent out of the gas tank, since ONE vent will still vent fumes to the canister and the filler neck.  Is that a bad plan. What year needed two vents? Was it carb specific years or emissions or did most years have two vents?

Thanks
Bud 

Extreme Parts Racing (more than just a haircut)

71TR6 CC57365 (Good 6)
71 Spitfire MK IV Race Car #3
69 Spitfire MK III (back up FE engine/dinghy car)
93 Minnie Winnie Race Support Vehicle 
77 Z-50A Hardly Davidson Honda Mini-Trail Bike (Triumph Pit Bike)