Drain for a flooded intake manifold to stop fuel filling cylinders in the event of a stuck float
On my 1948 Triumph Roadster built with a number of parts used on Standards, the copper tube was exactly as above. There was a male stud in the aluminium inlet manifold below the Solex carb. The copper tube was connected by brass nut and tube went directly down below sump level. There may have been a tab attached to one of the sump nuts to steady it.
How do I remember all this? One cold and windy morning car would not start. In haste I applied vigorous arm movements to the starting handle, the excess fuel blew back on to the hot starter motor and flames ensued.
Fortunately it was all over in a 'flash'. Cause? loose connection to the manifold. Result? I was late to work and had to buy a recon starter, my, those were the days.
