Jim, The way they're supposed to work is:
Port tank feeds Port engine, Stbd. tank feeds Stbd engine. No crossover, no fuel transfer, simple as that. Anything contrary to that needs investigation and would be a warrantable repair.
Agree with Dreamer--there is no way to crossover, since the tanks are below the bridge deck in the hulls. If you want to run on one engine, then try and equalize the time spent, so fuel burn will approximately be the same. We find that about 7 knots is the max speed on a single engine.
