I have a '65 Mercury 650 I recently got running after I think it has sat for quite awhile. Pretty much as soon as I got it to run a couple of the fuel lines from the fuel pumps developed leaks (no suprise due to age). I am wanting to build new lines from brass barb fitting and auto fuel hose. It looks to me like the original lines are "3/8 I.D. I was wondering if it would hurt to make the lines from "5/16 or even "1/4 I.D. fuel hose barb fittings and hose since they are a lot eaiser to find at the hardware store and a little cheaper. "3/8 hose is huge and seems a little overkill, but I really don't want to starve the engine of fuel either cause that could really be disasterous. I know people have done this before, but I would like to know if running a little smaller line would hurt anything.