starting issues with 1991 50 hp johnson

Hey, how is everyone doing? I am new to the community and already need a lot of help. Here is where I am stuck.
I have a Johnson 50hp outboard that will not run right, it runs for 2-3 sec and then dies. I have put new plugs in it this year and that is about it. Last year I had no problems with it. I tried bumping the choke after it starts and it runs, I have to hit the choke every 3 sec. and it keeps running but as soon as I stop with the choke the motor dies. I have replaced the fuel tank and lines as well as the primer bulb with a smaller portable tank. The old bulb wasn't getting hard when primed so I replaced it. This one seems like it is fine and it I guess is holding pressure b/c it is hard.
I don't know what to do with it, I did not do anything since last year and now it won't start.
Thanks in advance and any help is much appriciated.

Re: starting issues with 1991 50 hp johnson

Sounds like you are due for some carb cleaning. There are hundreds of posts on it, just do a search. Instead of choking it to keep it running try pumping the primer bulb. If it keeps running then it is most likely your fuel pump that has gone south. FWIW while you have the carbs apart to clean them you might consider getting a couple rebuild kits for 20.00 each and replacing the innards.

Re: starting issues with 1991 50 hp johnson

One other guy suggested the same, so I think I need to do some carb cleaning. thanks for the help

Re: starting issues with 1991 50 hp johnson

Agree with the carb bath/rebuild.

Pay close attention to the jets/orifices. The following may help, as would an OEM Service manual.

http://www.meegsonline.com/tmd/TMDsVideoChronicle2.wmv

Re: starting issues with 1991 50 hp johnson

Ok, I cleaned out the carb today, I soaked it for about one hour and then sprayed it with carb cleaner, at the end I used some air to blow it out.
This did not change much, it still idles rough and then dies. When I pull up the throttle it runs really rough. The piece of clear fuel hose shows some fuel that is flowing but there is definitely air in it. I am not sure if it is supposed to be like that. Also I tried squeezing the bulb while it is running and the motor still dies after couple of seconds.
I don't know what else to do.

Re: starting issues with 1991 50 hp johnson

did you follow these instructions? http://forums.iboats.com/showthread.php?t=244013

have you checked spark and compression. it takes these for it to run. proper compression, proper spark, at proper time, proper fuel, oil and air mixture. the spark and fuel mixture has to be proper synchronized (linc n sinc). the idle speed needs to be set at 600-750 rpms, in gear in the water. you may try to turn up the idle speed, and get it running.
the bolt bolt is the idle speed screw. turn it clockwise to increase throttle speed.

Re: starting issues with 1991 50 hp johnson

I did not check the compression yet , I will do that tomorrow. As for spark I would say it is good b/c the motor starts fine and runs but only for couple of second.