Fuel hose length concerns for 25 HP Merc 4 S

[TTipsword]

I am rigging out a new G3 welded 15 ft jon boat with a new 25 HP 4 stroke Merc (100% rated power). I intend to put a 12 gallon fuel tank beneath the forward deck to help balance the boat better, this will require approximately 10 ft of hose. Does anyone see a problem with this? My concern is if the Merc's fuel pump will have a problem pulling fuel through that much hose? I'm making the assumption that 3/8" is standard for this type application.

 

[TOHATSU GURU]

Re: Fuel hose length concerns for 25 HP Merc 4 S

Is it the new EFI 25 or the 2005 or older 25?

 

[jameservin]

Re: Fuel hose length concerns for 25 HP Merc 4 S

Think my jon tank was 16-18 ft long and didnt have any issues. I put the squeeze right by the controls and made starting easier.

 

[WillyBWright]

Re: Fuel hose length concerns for 25 HP Merc 4 S

3/8" is too big, but I doubt it would be a problem. You only need 1/4" for a 25. It would only be a problem if the tank were mounted very low in relation to the motor. The added weight of fuel in a 3/8" hose may be too heavy. But in most conventional boats, that could never be low enough to be of major concern.

 

[tashasdaddy]

Re: Fuel hose length concerns for 25 HP Merc 4 S

i have a 10ft hose on the 1955 15hp rude so i can put the tank forward. i have the old 2 line pressure tank, and have had no problems.

 

[TTipsword]

Re: Fuel hose length concerns for 25 HP Merc 4 S

The motor will be a 07 EFI, 25 HP. It seems that the most common fittings available are for a 3/8" fuel line - is that too big? I'm worried about the engine losing suction.. I don't know how robust the Mercs fuel pump will be.