Fuel line set-up for 2022 Mercury 250 Pro XS

[mac18]

I have a 1997 20' Cobra 201D and am considering a repower to a 2022 250 Pro XS. My current fuel line set up is 3/8" from tank to primer bulb and 5/16" from bulb to engine with no external water/fuel separator. My question is does the 2022 250 Pro XS use an external fuel/water separator in addition to the one in the engine? From searching some related posts I think the proper set-up would use 3/8" A1-15 from the gas tank to a water/fuel separator under the deck and 3/8" B1-15 from the separator to the engine with no primer bulb required. If that is right does anyone know the mercury model number for the correct water/fuel separator? Thanks!

[howieranger]

Mercury does not recommend an additional filter/water separator with the V8 4S. The filter on the motor is sufficient.

[EuropeanAM]

Actually, there IS an option for an external Water Separating Filter (with water in fuel warning). IF using an external filter kit, the under-cowl filter is REMOVED and replaced with a bypass fitting.

Under-cowl fitting is sufficient in most any application, provided that fuel supply is clean.

3/8" ID fuel line required from tank to engine (no primer bulb).

[mac18]

Thank you gentlemen, seems like a straight forward install then.

[ranger z520]

Can you keep the filter on the engine and use an external filter as well so you have double filtration

[EuropeanAM]

Mercury does not recommend utilizing multiple filters on the V6/V8 series engine. The recommended remote filter kit includes a bypass to be installed inside the engine cowling (where the previous filter was located).

[1BADAIR]

Bringing this back up. Should there be a fuel demand valve in the line?

[EuropeanAM]

Bringing this back up. Should there be a fuel demand valve in the line?

Depends on the BOAT'S fuel tank system. Most any built-in tank from 1/1/2011 and later will need some form of FDV in the system.

[1BADAIR]

Hmmm. Gonna have to do some checking. My boats a 2011 and my new engine will hopefully be here soon

[1BADAIR]

43DEF6E0-C9AF-4DEE-8A77-9660B4E397EF.jpeg
I don’t see a fdv on my tanks or anywhere. My caps say surge . Does that make it an open system?

[EuropeanAM]

What does the top of the tanks and pickup tubes look like?

Can't tell much from the fills/caps, but yes- it's an "open system" as long as the caps are removed.

[1BADAIR]

They are just 90 fittings coming out of the tank. Fill, fuel and vent lines for each tank as far as I can tell. Will try to get better pics tomorrow

[EuropeanAM]

That does not appear to be a pressurized system. Possible that your Ranger was built before 1/1/2011....