15hp Fuel Problems

Bakernator

Cadet
Joined
Jul 15, 2010
Messages
8
After getting my shifting issue fixed I took my outboard out for a spin on the lake this weekend. The last time I had it out it was running out of fuel so I thought the fuel pump needed to be rebuilt. I put a new diaphragm kit in the fuel pump, cleaned and rebuilt the carb, new fuel filter, new fuel and new plugs. What happens is that the engine will start up and run and idle fine, but when I open it up it will run fine for a couple seconds, then throttle up like its running better and then die out. If I keep the squeeze pulp pressurized it stays running, but I think now I might have a fouled plug because it wont seam to open up. I'm not sure where to go from here since the revving up before stalling out is telling me its too rich and getting a better mixture by starving but then starving out. I am not familiar with these carbs, but is there only the air screw adjustment? Anyone have any ideas to point in the right direction?
 

Nordin

Commander
Joined
Jun 12, 2010
Messages
2,428
What brand and year are we talking about?

Sounds like there is a clogged fuelline or tank pick up:
Have you cleaned the fuel line and tank pick up?
As you run out of fuel before the problem started the pick up might be clogged.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,924
After you check the stuff from Nordin.
Replace the fuel line and maybe the squeezie.
​Check for water in the fuel?
The inline connectors, replace or remove.
They have rubber in them and it can go bad and suck air.

Install a small clear filter between the carb and the pump.
 

fishrdan

Admiral
Joined
Jan 25, 2008
Messages
6,989
the engine will start up and run and idle fine, but when I open it up it will run fine for a couple seconds, then throttle up like its running better and then die out.

Sounds like the fuel quick disconnect is bad, the "throttling up like it's running better - then dying out" is the engine going lean then starving for fuel. Pump up the primer bulb and then hold pressure on it while moving the fuel quick disconnect and hose around, I bet you'll find fuel leaking at the fitting. If fuel leaks out, air will be sucked in, causing your problem.
 

Bakernator

Cadet
Joined
Jul 15, 2010
Messages
8
The outboard is a 1997 Force 15hp. I checked the connection from the motor to the fuel line as suggested and nothing leaked out when I tried to move it around. The squeeze bulb seams to stay firm, so I dont know if that would be the problem or not. There is a fuel filter between the motor connector and the fuel pump currently. I think my next step is going to be to change the fuel lines to clear lines so I can see where the fuel is not getting to. How do I check the fuel pickup line to see if its clogged?
 
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