50 D starves for fuel

[nautico 19]

Have twin 50 D on seagull cat hull tanks are located in hull around the water line. Engines are mounted approx 18" above water line. Lenght of fuel line to check valve approx 6' 6". Engines run below 4,000 rpm perfect for hours, take it above 4,000 and engines will loose power pump primer bulb they come back to life for 5 min then do the same. Have replaced fuel pumps, fuel bulbs, fuel lines, fuel filters and check valves. Have removed carbs and cleaned, No air in fuel lines. Was wondering if these engines cannot lift fuel to this height?

 

[TOHATSU GURU]

Re: 50 D starves for fuel

The engines can pull the fuel from the deck. The problem may be at the tank itself. I find it difficult to believe the fuel pumps were changed since they are built into the carburetor body itself and cannot be replaced. What dealer is doing the work on your engine?

 

[nautico 19]

Re: 50 D starves for fuel

The engines can pull the fuel from the deck. The problem may be at the tank itself. I find it difficult to believe the fuel pumps were changed since they are built into the carburetor body itself and cannot be replaced. What dealer is doing the work on your engine?

 

[nautico 19]

Re: 50 D starves for fuel

my mistake, I rebuilt both fuel pumps,new diaphrams and reed valves. Have two tanks both tanks have 12" siphon tubes they are in, place and tested for leaks. Installed clear tubing from primer bulb to engine no air. Will these engines pull fuel from the hull? Bought boat 2 years ago always have had this problem.

 

[TOHATSU GURU]

Re: 50 D starves for fuel

The engine will pull the fuel a lot further then what your trying. Since the problem is occuring with both engines it has to be a fuel supply issue of some kind related to your setup. IE It's from the engine to the tank. Get two portable tanks and run the engines from those. If everything works than you know its a fuel connecter, hose, primebulb or tank problem.

 

[TOHATSU GURU]

Re: 50 D starves for fuel

Just a thought..You do have two 3/8 seperate fuel lines with two separate primebulbs right? If you have one primebulb and then a fuel line split to both engines you can't draw enough fuel.

 

[nautico 19]

Re: 50 D starves for fuel

Just a thought..You do have two 3/8 seperate fuel lines with two separate primebulbs right? If you have one primebulb and then a fuel line split to both engines you can't draw enough fuel.

 

[nautico 19]

Re: 50 D starves for fuel

Have two tanks two fuel lines two filters two primer bulbs replaced everthing same problem removed everything and tested lines for leaks. Everything tested good replaced with same problem.? Guess I'm still missing something.

 

[TOHATSU GURU]

Re: 50 D starves for fuel

What does your local dealer think?

 

[nautico 19]

Re: 50 D starves for fuel

What does your local dealer think?

 

[nautico 19]

Re: 50 D starves for fuel

local dealer roman, says add fuel pumps did that runs better than new problem solved thanks.

 

[TOHATSU GURU]

Re: 50 D starves for fuel

Roman Kruk is a genius.