15 hp Johnson won't idle at low speeds

[bassplaya]

1992 15 hp Johnson. the only way the motor will idle is at high speed with the choke about a 1/3 out. I found a crack in the float bowl and replaced that. Seem a little better, but not right. Carb was supposedly just rebuilt, but wasn't done by me, so who's to say. Lets say it was. It acts like it is getting to much air. With it idling high, I can plug the air intake with my fingers(not completely) and the idle goes up even higher. But, if I lower the throttle, it dies pretty quick. This is all done with the choke out about 1/3. Even running at high rpms, if i open the choke up all the way, it dies pretty quick. Motor will run all day if the choke is left at 1/3 closed, but has to have high idle. Any suggestions?

[bassplaya]

ok, carb has difinitely been cleaned now and new gaskets installed. A little improvement, but still needs choke and doesn't idle slow.
Two things I noticed: the new needle valve retainer is not threaded and is a tight fit. Installing the needle valve was challanging. I tried to use the end knob, but that stripped out instantly. I had to use channel locks to screw the needle valve in. (now of course the end of that is ruined)( what a crap design).
Second thing I noticed was the top body cover (which is plastic), doesn't form a tight fit in the upper right hand corner.
I have read this could cause a problem.
One solution was to drill and tap that corner out and install another 8/32 screw.
Only problem with that is, if that doesn't work, the carb is now junk.

Do they make an after market cover or is there another solution.
It sure seems strange that the cover isn't seated there.

[bassplaya]

ok. Its fixed

Top carb cover is warped. But that wasn't the problem. Sorry design.

The hole where the needle valve goes is worn out also. The needle valve was going in way to far. By about 5 turns. Once I found this, I readjusted and it starts right up and runs great.