engine specs and pinched hose????

[rolex_26_99]

Hey guys new to this forum and pretty new to volvo engines.

I have a few quick questions about a pinched hose in the picture, fuel consumptions and general reliability of this engine.

First off. Can anyone tell me what the hose that is pinched is used for?

And secondly this engine is in a 1997 four winns 258 with a duo prop drive that weighs around 5300lbs.

What kind of consumptions should i expect?

I currently have a carburated volvo 5.7 that gives me around 16 liters per hour at 2800 to 3000 rpm

Thanks for the info