I have a '95 Evinrude, 50hp and I am having a problem with it. It use to be that in order to start it, you had to choke it once with the key, then you couldn't choke it again or it would flood it (this is what I was told). Now the problem I have been having is this. The only way I can get the engine to start is to choke it every time I turn the key. If I don't choke it, then it just keeps turning over and it never fires. Then once I get it started, I have to hurry up and put it in forward to keep it running. This takes several tries before/if it works. But once it starts going for about 5 to 10 seconds, it dies.

The other part of this situation is that when I finally get it running, I give it full throttle and it only goes at about 25% of its normal speed and power. After several minutes of running it like this, then it will suddenly open up and be fine. Once it opens up, then I have no problems with it until it sits for a week or two. Any ideas what this is? Thanks for taking the time to read this and trying to help me?

I haven't had this problem with an outboard but when I had a dirt bike I had something similar happen.  My advice is to start diagnosing it in steps.  

1. make sure that the fuel is fresh

2. make sure the fuel bulb is firm

3. change the fuel filter

4. clean the carbs out, make sure there are no loose fuel lines or vacuum lines.

5. change the spark plug

6. give it a Sea Foam treatment

7. adjust or have a pro adjust the carb

Don't know if this helps but it usually worked for me.  Like I said my dirt bike sat for over a year while I was in Iraq.  And I pretty much went through this process and finally got the bugs out.

Good Luck,

Danny

The first thing you need to check when it's doing this is to make sure both plugs are firing with a good strong spark. They should be able to jump a 7/16" gap on a plug checker. I've had a number of power packs that will quit firing after sitting for a while. Get them running and after a short run period they would kick in and run on all cylinders. As long as you used the motor regularly, they would not give a problem but let it sit a few days and back to the hard to start and running like crap until they kick in.

If both plugs are firing, I would pull the carbs and clean them and do a link and sinc on it.