2000 25 hp Johnson 2 stroke

[sova04]

Have a 25hp johnson outboard that im getting ready for winter, after several pulls i got her running with lower in a 55 gallon drum with hose on keeping it full. After maybe 30 seconds of running the motor appeared to do a "sucking" coughing sound out the exhaust hole and immediatetly stalls. It will start back up and do it again weather its in neutral or in gear. I noticed last year before putting her up for the year when fishing on the pond it would periodically start running like crap and smoke. But it would clear itself up, I've cleaned the carb and replaced fuel lines from the tank to the motor including the primer bulb. The plugs and wires are also new. i took the fuel pump apart to check and see if the diaphram was compromised and it didnt appear to be defective. i did not however notice an o ring that is on the connection single screw connection to the fuel pump from tank had a tear, I will be replacing that tomorrow but could it be that? If not what should my next step be? I currently have a water pump replacement kit on the way with new impellar because i do not know when it was last changed.
Any advice is greatly appreciated.

 

[racerone]

Sounds like a ---" lean sneeze "-----A much misunderstood thing on 2 strokes.----Open slow speed mixture screw 1/4 turn at a time.----Also caused by throttle plate opening too early.

 

[oldboat1]

^agree. Not sure what the sucking sound is, though. Water level in the barrel should not be over the exhaust port -- need enough to cover the pump by 6 or 7 inches. I usually fill about half way up the shaft.

Actually, you probably could get a sucking sound if the water level is too low. Check it.

 

[sova04]

^agree. Not sure what the sucking sound is, though. Water level in the barrel should not be over the exhaust port -- need enough to cover the pump by 6 or 7 inches. I usually fill about half way up the shaft.

Actually, you probably could get a sucking sound if the water level is too low. Check it.

the water level is good it seems to be worse when i start in lowest possible forward position and then pull back into neutral. I have been adjusting the screw on carb and seems to be better than yesterday but still doing it. I am going to put in the pond tomorrow and see how it acts compared to the 55 gallon drum.

 

[sova04]

the water level is good it seems to be worse when i start in lowest possible forward position and then pull back into neutral. I have been adjusting the screw on carb and seems to be better than yesterday but still doing it. I am going to put in the pond tomorrow and see how it acts compared to the 55 gallon drum.

 

[racerone]

The---- " sneeze "--- Might occur in the exhaust housing.-----The sudden rise in pressure pusher water down and out of the exhaust housing.-----Then water floods back in and makes strange sounds I think.