Johnson 25 hp lean sneeze.

[Bendellaria]

Ok so I'm hoping someone can help me. I have a 1993 Johnson 25 hp. Electric start. And after it warms up it will have a lean sneeze from what I can understand and then it will stall hard and after a few times of it stalling it gets harder to start it only does this at idle. Once I get it started it will run fine off of idle and always runs fine off of idle top end is plenty of power. I have replaced plugs thermostat and springs. Gone through carb and removed welch plugs to clean ports. Checked leaf valves in intake. Retuned carb a million times in water under load. I used acetelyne torch to find vacuum leaks on case or seals seemed to be problem at lower crank seal removed power head and re sealed lower crank seal along with upper crank seal. But still have no luck getting this to run correct at idle any info would be appreciated. Thank you

 

[kbait]

Check/replace #10 and 13 o-rings in carb schematic for your motor. Go to marineengine dot com and find your model.

 

[Bendellaria]

Thanks for your reply but like I mentioned in my post I went through the entire carb with a factory rebuild kit which had the o rings for the mixture screw and the seat for it.

 

[racerone]

Perhaps throttle plate is opening too early.-----At the back of that long thin rod there is an adjustment / stop.-----Is there a gap of about 3/16" at idle , yes or no ?

 

[Bendellaria]

At idle the plate is closed because there is a notch at the top for pre determined amount of air to be allowed when at idle and if it were opening to early then my problem would not be present because I said it does not have the problem off of idle only at idle in gear or not in gear doesn't matter only when idling in a no wake zone constant sneeze every 4 seconds or so then will sneeze and stall only when warmed up it is not over heating at all

 

[Bendellaria]

It seems most carbs are like you mentioned racerone. But mine isnt not sure why I do know the carb is correct for this model but it is not a common carb at all.

 

[racerone]

????----So are you going to try and determine if the throttle plate is opening too early ?----I have a bunch of these 2 cylinder motors and understand how they work !!

 

[kbait]

Sorry, you never mentioned factory rebuild kit. Plug primer port at carb base and test.

 

[flyingscott]

Put up a pic of the carb. Does your carb have 1 or 2 low speed screws?

 

[Bendellaria]

Ok so racerone how should I double check the if the plate is opening too soon I'm basing it off that fact its idling the plate is closed at this point and this is when the problem happens. Flying scott only 1 screw and yes kbait I used a factory kit complete overhaul multiple times on water with attempting to adjust it only has one air screw which is behind the throttle plate I start at 1.25 turns and go from there if I'm doing something wrong please tell me I am an automotive tech so I have knowledge and therory just not much in outboards

 

[racerone]

See post # 4

 

[Bendellaria]

So I see nobody here is helpful especially racerone your an idiot dont be ass to people actually asking a question. I'll find advise some where else admins please delete this post if you can

 

[flyingscott]

Good luck with your motor. Take.your motor to a dealer as a link and sync seems to be beyond you.

 

[kbait]

So I see nobody here is helpful especially racerone your an idiot dont be *** to people actually asking a question. I'll find advise some where else admins please delete this post if you can

Wow..
So, you’re an automotive tech? Hope you don’t deal with the public..your people skills suck!

 

[oldboat1]

Assuming the l.s. and h.s. orifice plugs are clean and snugged down, the idle needle needs to be opened slightly to allow a richer mix. Adjust 1/8 to 1/4 turn at a time, and give the motor a little time to catch up. I’m not sure what your manual specifies as the initial setting — might be more than the standard 1 1/2 turns on older carbs.

There’s at least one lead plug up there, and that needs to be replaced if it was removed. I usually open up and disassemble the carbs and soak top and bottom in lacquer thinner — followed by thin wire in every opening and a shot of carb cleaner. I normally leave the jets in place as they are easy to damage during removal and replacement.