I'm checking out both my ignition and fuel systems, my 1979 OMC 120HP inline 4cyl loses rpms to the point of stalling, after she heats up around 160F (about an hour out).<br /><br />I replaced all plugs, plug wires, and I'm just being stubborn about replacing the coil until i can figure out how old this one is, or get desparate, whichever comes first.<br /><br />As for fuel, i'm going to check for clogged gas tank vent, check the fuel filter, and for water in the system. My question is what is the clear cylindrical thing inline in the fuel line just starboard of the engine (about 3-4 feet shy of the carb)?<br /><br />Is it a water separator? a check valve? are these one in the same? It lays horizontal inline in the fuel line, but when i pick either end up it dribbles out what appears (looks, smells, i haven't tasted it yet) to be gasoline. Inside the clear plastic? tube is what looks like a little filter.<br /><br />Thanks for any help!