1948 Scott Atwater 481 3.6HP starts and dies

[rg16242]

Hi all,

I am new to the site and am hoping to get some advice on my '48 Scott Atwater. I picked it up in the fall and it ran great in the barrel at high speed and idle for as long as I wanted. Now I just pulled it out to test before a trip to the lake in a couple weeks, and it fires right up on the first or second pull with the choke pressed, but it coughs and dies within a couple seconds. It will do this over and over again as long as keep restarting it. I can actually get it warmed up by repeating the process many times. I pulled the carb apart and soaked it for a few days, and then I poked a wire into all of the ports that I could see. It was very clean to begin with though. I adjusted the high and low speed carb valves all over the spectrum and I can't get it to stay running. It has a new plug and pumps water great. I don't know what could have happened over the winter to cause the problem. Thanks in advance for any tips!

 

[ronboonville]

Make sure the fuel valve and line are not plugged or partially blocked. Try screwing in the idle screw all the way in. Before cranking flood the carb by holding float pin on carb down for a few seconds. I use a variable speed drill on flywheel nut to save my arm. When all that fails I clean the carb again. also I remove the welch plug and clean those little holes there.

 

[twocyclemania]

I have a few of these Scott and Firestone motors with tanks on top (from the same era). I have had similar problems. I have noticed that when I went to test them and only had a small amount of fuel in the tank I had the same problem. Make sure you have plenty of fuel and the gas cap valve is open. Make sure that the fuel is flowing freely from the gas tank/valve/gas line. A good indicator of it not getting enough fuel is the float pin (mentioned by ronboonville) on the carb bowl being bottomed out. It should be 'popped up' all the time which would indicate you have fuel to the bowl.