Help Identifying part on johnson 25 hp

[Borgey401]

Please inform me on what this screw on the carb does. The one in question is the one with the red ring around it in the picture. My father decided it would be a good idea to play with it without knowing what it was since my motor was idling a little rough. It seems to be idling even more rough now. I think it's the slow speed adjustment. Motor is a Johnson 25hp 91 model # J25ELEID

http://i839.photobucket.com/albums/zz315/borgey401/boat/IMG_20110702_183445.jpg

 

[Daviet]

Re: Help Identifying part on johnson 25 hp

Low speed needle valve. Static setting should be 1 1/4 turn out from lightly seated and final adjustment made with the boat in the water and in gear.

 

[Borgey401]

Re: Help Identifying part on johnson 25 hp

I'm sorry but I am not too sure what you mean by "lightly seated"? I have no idea where it is set to as of now. But I am pretty mad that he went and played with it without knowing what it was. I mean it can't be too hard to figure out and get it fine tuned I'm just not sure how to go about doing it since I am new to boats.

 

[Daviet]

Re: Help Identifying part on johnson 25 hp

Lightly seated = Screw it in gently until it makes contact and then stop, do not try and jam it in.
Then screw it back out 1 1/4 turns and then adjust it in the water with the boat in gear until it runs the best.

 

[Borgey401]

Re: Help Identifying part on johnson 25 hp

Thanks so much Daviet. I am sorry to bother you with such newbie questions it's just I am learning. Once again I really appreciate you taking the time to help me out.

 

[Maggie Mae]

1989 30 hp Johnson sputtering when start

1989 30 hp Johnson sputtering when start

Just bought a 1989 Lund alaskan with a 89 Johnson 30 hp , the guy told me when you start it and on idle starts the sputter. First time I started it and turned the throttle and then brought it back down to idle it stalled. After that started it again fired right up and sputter a little bit then stopped then would do it again. I was told it might be the rich to lean controls might need to be adjusted, or carb needs to be cleaned.

 

[Daviet]

Re: 1989 30 hp Johnson sputtering when start

Re: 1989 30 hp Johnson sputtering when start

Maggie, you should start a new thread of your own so that you will not get lost on the end of an old post.
That being said, it does sound like you might need some carb work. You might want to do some easy checks first, make sure the compression is good on both cylinders, make sure the spark will jump a 7/16" gap and be bright blue. There is a low speed adjustment on your carb, you might try opening it up a 1/4 turn and see if it helps.
If all the above is good and the adjustment doesn't help, it might be time to over haul the carb.
Oh, by the way, welcome to the forum.