8HP Johnson Idle Problem

[Blackdog]

I need some help with a 1989 8HP Johnson. It starts good but will not continue running unless the choke is over half closed. The carburetor has been taken off and cleaned with compressed air and carburetor cleaner. New fuel lines have been installed and the fuel is fresh. Compression is 95 and 105 and there is a good spark at the plugs. The fuel pump appears to be working OK. I feel like there is a problem with the carburetor. Any suggestions will be appreciated.

[bassplaya]

Boat Parts

This sight has a complete breakdown of your carb.
I just fixed my 15 hp Johnson of the exact same problem.
Soak overnight in carb cleaner
Rebuild with kit.
You will replace the flex tube, which is your slow idle tube.
Ensure the tube is clean in carb.

Is your top carb cover plastic? The plastic ones will warp.

My problem was, the top carb cover was so worn, the needle valve was going in to far, so my adjustment was all wrong.
It doesn't look like your carb has the same needle valve, but I don't know your exact model.

So i would really concentrate on the slow speed passage and have no doubt that it is clean.

[Blackdog]

Thanks Bassplaya for the info regarding my problem. It all sounds plausible and I will certainly pursue it.