91 50hp johnson won't idle, (rebuilt carbs) I can get it to start when throttled up but will die after a few seconds, but if I hit the choke it run a little longer, won't run without throttled up?
Clean, clean, clean, clean the carbs really good and make sure every orifice jet is completely clear. Reason I say this is you might not have gotten it the first time cleaned as good as you thought you did. Also check the fuel lines for fuel leaks. Let us know what you find out. Take care, Bob
You've got good compression (other thread), and good spark (assuming it runs fine at high speed...), than all that is left is fuel delivery. Check for air leaks in the lines, make sure the spark plugs are clean, etc. When the carb was rebuilt, was the welch plug (#5) removed and all of the tiny idle passages cleaned out?
The (#7) nozzle gasket needs to be in real good shape also
I have had a lot of idle problems with my 85' 115. I corrected some issues by adding a clear inline fuel filter from Walmart. I then could see that is was running out of fuel and not staying full after pumping. Using an air compressor I found a small leak near the bulb. Fixed the leak and Fuel delivery is not an issue anymore.