15hp 2atroke problems

[airlock]

First of two posts, I’m afraid my old 2banher isn’t happy.
It’s always run “ok” a few hiccups when warming up and cut outs every now and then but it always got there and ran clean after it was warm.
Last two trips out it’s statted to cough, splutter and die when the revs dropped and then only got home by using half choke and idling along. Any extra revs would kill it and restating was a long game.
Cleaned the plugs and drained the bowls, ran well for the first trip and then the same problems appeared.
Plugs are piling up even when using a very lean mixture, smoke seems to fluctuate between black and bright white (water?) and the engine dies under load.
If like to avoid a costly repair bill as it will end up costing more then the motor so any pointers would be great, but if she’s not going to make it I’d rather invest in a newer model then pay to repair the old girl.

1995 Johnson 15.

[fishizzle]

i’d shout her a new set of spark plugs and make sure the fuel is fresh and clean.

[Noelm]

Remove the carby/s clean them properly, don't spray them or just look at them, they must be properly cleaned, new plugs, go boating.

[airlock]

Off to the garage it is then!

[stevej]

as noelm said get the carb rebuilt
stripped ultrasonic cleaned and rebuilt

simple engines, all you need is compression spark and fuel

[GBC]

Sounds like crap in the needle. Trace wire up the inside works well to clean them.

[gazza2006au]

When u clean out the carburetor u also need to clean every drop in the fuel tank and also pull your fuel hose apart and pour out all the fuel inside of it i own a lot of smaller boats with portable tanks i find a lot of water collects inside the fuel primer, the fuel goes like jelly and some dirt from the tank also gets caught here

if u clean the carburetor than leave the hose and tank your likely just going to have the same problem, when u clean the carburetor remove the idle jet and main jet and blow thru it with compressed air and or use a piece of copper wire just bend a few strands back enough to fit thru the jet

forgot to mention when u pull the carburetor off try and keep it in a upright position while u undo the bowl so when u get the bowl off u can look for jelly substance or water floating on top of the fuel pour it into a clear clean container and examine

good luck

[BM]

Having to use the choke partially to keep it running says that its starving for fuel so cutting the air restores the fuel/air ratio to some degree. Either it's running lean or has a fuel flow issue.

I would compression test the engine as a starting point. No point doing anything else if you have compression issues.

Black smoke sounds a bit odd. Typically a 2-stroke will give of blueish to white smoke.

[paullee]

Is the fuel line and or primer bulb brittle? The cheaper ones delaminate from the inside and deposit all the crap in to the carby.asthey said above, clean the tank and carby but also replace the fuel line and primer or the same might happen again....