DB6 volante CHECK VALVE

[TRfan]

Does anyone know exactly why the fuel check valve is in the DB6V fuel circuit ?

If you are drawing fuel from the reserve tank it doesn’t go through a check valve, so why is it needed on the lhs main tank line.

I ask the question because when I am switched to main tank I get fuel starvation after a mile or so. This seemed to me to be a breather problem, but that has been checked and is AOK. That only leaves the Check Valve as a suspect.

Any comments welcome

Thanks. Jb