1948 B12 gas tank vent

[BIGDAVE]

This B12 I'm working on has the gas tank vented by copper tube up to the top of the engine compartment then back and exits straight down above the rear wheel.  Looks like a good place to plug up with ice/snow.  Any comment?  I have been working on a fuel supply issue.  The tank is out and rinsed.  I put a Polaris snowmobile pick screen in the tank and plan to put a strainer/sediment bowl immediately outside the tank, then there is already another in line filter.  Haven't been into the carb, but plan to lift the top and take a peak in there.
            Thanks, BIGDAVE

[48bomber]

The problem with mine ended up being the carb. The fuel filter change and checking the fuel pump made no difference to the way mine run. A carb kit was $80.00  a hole new carb was 160.00.  Within 5 min of installing the new carb I had a perfect running engine!
  The local auto parts store had no problem getting the carb.
  If your fuel does not make a difference consider this as an option.
  Let us know how you make out!!
   48bomber