Need Help with Mercury 20 HP Running then Quitting

[onemachine]

I have a mid-70's Mercury 20 horsepower 2-stroke (It's a "Merc200" with "Super Hurricane" I believe). It takes about 20 yanks on the cord to get it started with choke fully on. After its started I have to immediately take off the choke and give it some throttle to keep it running. If I try to back off on the throttle to get it to idle it will just die. So, I leave the throttle half open and it will run like this at high RPM for about 10 to 20 seconds, but then it will abrubtly quit. To get it started again, I have to yank on the cord another 20 or 30 times with choke fully on. The same thing will happen over and over.

What is going on!?!?

I'm sure it is a fuel/carburetor problem. I am squeezing the fuel pump bulb plenty of times to give proper fuel pressure, etc, etc. BTW, the engine did run (and idle) fine when I had it on the lake 2 weeks ago. A couple times when I had it out it would do something similar where it would start normally then die after about 20 seconds, but then it would run perfect after starting again...this seems like it may be the precursor to the major problem I have now, but not sure.

Thanks for your help!

 

[onemachine]

Re: Need Help with Mercury 20 HP Running then Quitting

GOT IT! I figured it out...

So this Merc has one of those fancy quick-connect fuel lines that you press on, twist about 1/4 turn, and it locks on. Well, before this problem happened, my fuel connection was leaking so I just took the quick-connector off and slipped my fuel line directly over the male end on the engine. What I realized -- 5 minutes after submitting the above thread -- is that there is a little valve inside the male end of the fuel connect on the engine. The female side of the connector (which I removed because it was leaking) presses on the valve and allows fuel to flow through. Since I removed the female side the fuel line was essentially clogged. I fixed this and the engine runs fine. Perhaps if anyone else has this problem they will stumble across this thread and it will save them from tearing apart their carburetor (which I was about a fifth-step short of doing before I realized what I had done). Cheers!