Outboard running rough suggestions

[SharpStix]

Sorry darralld... I am not the OP, I saw the question you asked and realized I had mistakenly said carbs when providing details of a similar experience. I am not sure if the OP is dealing with carbs or EFI.

[d_e_smith]

Is it hanging up at a certain RPM level?

[Jaybo31]

What motor is it?

Change the plugs and all the fuel lines. If you have a fuel line that has become damaged due to ethanol it will do this. Idle fine and run fine at low speed. Start sucking more gas and the inner liner will collapse and cut the fuel supply off.

[knighttime]

You guys that have encountered this problem is there a replacement hose you all prefer over the others; like is there a hose out there that performs better against ethanol than others?

[denowt]

I'd remove the year old gas as a first step.

Next step, I'd see if you could find a buddy with a fairly new portable tank and fuel lines and see how the boat runs with that.
If it still runs bad, then you probably have engine problems.
If it runs fine with the portable, then put new gas w/ marine Sta-Bil in the boat's tank and see what happens.

[d_e_smith]

My similar problem was a bad tach that made the gov kick in. Almost created a mountain out of that mole hill assuming the worst.

[SaltwaterSlick]

Excellent advice in this thread. Give us a few more details and we might be able to narrow it down a bit for ya... such as float valves stickin' old fuel lines deteriorating, collapsing, filters clogged... etc.

Brand, size year model, HP of outboard?

[scott1022]

Long shot, but also remove the prop to make sure there is nothing wrapped around the drive shaft. Grass, fishing line, etc...

[ultralite09]

The boat is a 2002 Carolina skiff, Not sure what year motor but not too too old. Mercury 150 hp 2 stroke. Injected with the oil reservoir under the cowling. I pumped the bulb while running as well, it would help a bit but still cut out. Gonna replace the fuel lines that we can see and a new bulb if that helps.



The tank is real hard to get to so trying all other options, before having to do major repair.

[ultralite09]

Bump

[darralld]

Run a hose down the gas tank fill hose and siphon all you can out of it. Trying a small external tank & gas line is a great idea. Would narrow down if it's fuel line or motor related.

[SaltwaterSlick]

Before you remove all the lines, since you're going to change them any, take off the fitting where it connects to the motor and hook up a small bilge/sump pump and see if you can pump out the gas from the tank. Or use the bulb to pump out the gas. That line should allow you to pretty much get all the liquid out of the tank. Would be the same as the motor sucking the gas out... just sort of thinking/typing "outloud"...

First thing I'd try would be an external tank/hose and see if the motor runs good with it... Might save you a lot of time.

[SB09]

I think it's the carbs. It's obstructed somewhere, just not enough to cause the engine to not run at all. When you put a load on the engine it increases the fuel demand. The fuel supply cannot replenish fast enough and the boat falls on it's face starving for fuel. Seen this same thing many times over with the introduction of ethanol.

Especially with you talking about pumping the bulb helping it. Exact set of symptoms I've seen on other motors needing cleaning/replacement. You're increasing the pressure and sending more fuel to the motor. Which is compensating for the obstruction momentarily. That eliminates an air issue as a possibility too. It's a fuel problem no doubt. I'm 99% sure it's a carb problem.

[BowSlayer]

I think it's the carbs. It's obstructed somewhere, just not enough to cause the engine to not run at all. When you put a load on the engine it increases the fuel demand. The fuel supply cannot replenish fast enough and the boat falls on it's face starving for fuel. Seen this same thing many times over with the introduction of ethanol.

I doubt it's the carbs.....since it doesn't have any.

[SB09]

I doubt it's the carbs.....since it doesn't have any.

Second thought, the way he is talking about pumping the bulb and the oil reservoir I think this is a carb engine. If it was injected why would the system need to be primed with the bulb? Fuel injected engines prime themselves I thought?