2019 DF25A not running to potential

[hillbillyfab]

Bought this little engine in the later part of 2019 brand new. Put a hour meter on it when I hung it on the transom. It has approximately 7 hours on it. The little engine has ran fine except the past couple outings. It runs well from a cold start away from the ramp, but then it acts like it's starving for fuel. I can pump and pump on the hand primer and it'll start to pick back up, rpm and speed wise, but it won't stay running like it's supposed to. I've also shut it off and waited a few minutes and it'll run well for just a little bit then start acting up again. Going to change the fuel filter(blue one) and start over with fresh fuel. Is there anything I'm overlooking? I traced the fuel line from where it enters the engine, to the blue fuel filter, then to the engine mounted fuel pump. There's only one filter correct? Also the stream on my engine, looks good, but it's there anyway to verify my water pump is meeting expectations, other that tearing into it? Thanks for any and all advice in advance.

[Moonlighter]

Have you checked the tank vent?

If the primer bulb is getting sucked flat, then the fuel flow from the tank to there is being restricted by something - the tank vent is closed/blocked/vent hose is kinked etc. or the tank pickup is getting restricted, maybe by contamination in the tank.

Have a look at those things.

I always recommend that people install a water separating fuel filter between the tank and the bulb, a proper one like a Racor. Getting contaminated fuel into the engine filters is a PITA that can get expensive, and can be largely avoided by using the Racor filter and changing the element every couole of years or every 100hrs whichever comes first.

[hillbillyfab]

Have you checked the tank vent?

If the primer bulb is getting sucked flat, then the fuel flow from the tank to there is being restricted by something - the tank vent is closed/blocked/vent hose is kinked etc. or the tank pickup is getting restricted, maybe by contamination in the tank.

Have a look at those things.

I always recommend that people install a water separating fuel filter between the tank and the bulb, a proper one like a Racor. Getting contaminated fuel into the engine filters is a PITA that can get expensive, and can be largely avoided by using the Racor filter and changing the element every couole of years or every 100hrs whichever comes first.

I actually took the cap completely off the fuel tank, when it started acting up. It didn't seem to make a difference. I've pulled the quick connect off the engine side of the fuel line and it squirted fuel everytime I squeezed the bulb. So I think I'm good from my tank to the engine as far as fuel goes. I do not have a water separator between the fuel tank and engine. I'll have to look into adding one, especially with the quality of fuel that's on the market.

[hillbillyfab]

Wanted to update this.

Changed the fuel and fuel filter. Same symptoms out on the water. I can squeeze the primer bulb and the engine tries to pick speed back up. Gonna to swap out my fuel line and primer bulb with another known good one and see what happens. How could I test the fuel pump on the side of the engine? Is there a certain amount of pressure it should build?

[hillbillyfab]

Alright new fuel line and primer bulb, still same problems. Let my son operate the tiller handle, while I pumped on the primer bulb and the little engine picks back up and runs how it should as long as I keep pumping. I really think it's the fuel pump giving me fits.