Boat sputters under load (05 Johnson 2 stroke)

I’m seeking insight into a current problem that I have; this weekend I dropped my boat in the water could barely pull off the trailer and attempted to accelerate and couldn’t get over 5-8mph. The engine would spit and sputter and fail sometimes cutting off (like it’s being choked out of gas). However, when I put the boat in neutral and reved the engine in gear it sounded strong without any spitting at all.

The motor is a 2005 Johnson Ocean Series (2 Stroke). I’ve read that the power packs fail on these motors somewhat consistently which causes the motor to only run on 2 cylinders… Recently, I just got the boat back from the shop where they replaced a rectifier regulator to get the engine running. Also, the tilt/trim went out but the mechanic “jolted” it with a volt meter and got it running again. Everything screams electrical to me…but I’d like to some further insight/help from you guys.

One last thing, which scares me the most…when I pull up the lid to get into the transom of the boat in the bilge pump area, it reaks of gas. The mechanic said that is due to the fuel lines that he replaced but I’m not so sure…

Any help is much appreciated. If anyone cares enough, I took a video that I could email that displayed the poor performace this past weekend.

Thank you for any insight!

Fuel odor in bilge means fuel leak.

Volt/ohm meters measure electrical characteristics…they do not “jolt” anything.

I am not a mechanic, I don’t think yours is either.

but the mechanic "jolted" it with a volt meter and got it running again.

That didn’t happen :smiley:

Probably ethanol fuel and gunked up carbs.

Find the source of that fuel leak, if there is a leak in the system it could be sucking air and causing that problem, but a fuel leak is nothing to fool around with. Your first priority over the engine problem. A very slight odor of gas is normal, more than very slight is not.

If it is sucking air, the engine will run too lean and might burn a piston too. Fix the fuel leak first.

Capt. Larry Teuton
Cracker Built Custom Boats

“Ships are the nearest things to dreams that hands have ever made.” -Robert N. Rose

So with out knowing a thing about your motor, I wil ask the obvious adout historic service; compression checked? spark plugs? Clean carbs? ( unless injected ) fuel filter? timing checked? coil packs checked? Primer bulb? ( yeah the little thing you squeeze) spark advance set correctly? If all that checks out, maybe the trigger, rev limiter? 2005 model should still be pretty basic stuff.

I would check with a decent mechanic. Just sayin’

Cracker Larry thanks for the sound advice. Sparker all the compression and other things listed checked OK. No idea about the carbs…thinking of draining the carbs first to see what comes out and depending on that moving to rebuild the carbs. Any suggestions what to do along the way?

My experience with this exact problem was the stator and trigger

Reel tight: thanks, not knowledgeable about that or what its for but will do some research, thank you.

Take it to chrisv at Charleston Marine.

We have a 2006 Johnson 2-stroke and had a similar problem on 2 occasions. The first time was due to a pinhole leak in the primer bulb and there was a faint gas smell at the transom. The second time it was due to the carburetor float bowls becoming warped and sucking air. Both situations involved a problem with the fuel delivery. I hope you just have a bad primer bulb. The carb fix was pretty expensive. Good luck.

Pioneer Venture 175, Johnson 90
Summerville, SC

The other reason you may be smelling gas is due to unburned fuel that comes out of the engine when trimmed up. If your engine isn’t running on all cylinders due to an electrical issue, or your only getting occasional fire on one of the cylinders there will be unburned fuel left over.
Im with you on the electrical issue. I have a 97 Merc 2 stoke that is doing the same thing. I have spent well over 1,500$ in mechanical work/parts and its still not right. Losong some faith in local mechanics i’d hate to say.
Compression is good, new stator, new trigger, coils were replaced, new fuel lines and bulb, new water fuel separator, carb job and still old problem still there.

The rectifier really only deals with charging your battery while the engine is running. I found the stator and trigger wires were smashed behind the starter on my boat after the last mechanic put it back together, they overheated and shorted so my fear is that my new stator or coils got cooked due to all of that high voltage shorting on the block.

Anyways based on my experience with a similar problem it seems electrical, I’m willing to bet your engines not running on all cylinders thus the lack of power to get over 8mph.
Engine probably chokes itself out because its getting flooded.
Ive got mine in to another mechanic, i’ll let ya know if i get good results and recommend them to you.

You have two ears and one mouth, science would say you should listen twice as much as you speak.