Surging and dieing

[DanielV2]

I have a 1970 cub that is giving me some trouble. It is surging at idle speed. It will settle out of I keep the throttle in one place. I cleaned the carb, soaked in Berryman's and blew out all orafices I could find. Now it is exhibiting a slightly different problem. After it warms up, it will run for a minute or so, surge real badly and then die. If I try to restart immediately, it won't start. If I count till 10, it will restart and run for another minute. If i let it sit for longer, it will run a little longer before surging and dieing again. Fuel starvation? Thinking about blowing out the carb again and checking the fuel bowl below the gas tank. Anything else I should be checking?

Thanks!
Daniel V

[SONNY]

Try it with the choke pulled out part/all the way and if this helps, it sounds like carb.---if it don't help then check governor for wear /adjustment.
check inside the gas tank for something floating around,--gas cap vent holes too sounds like major fuel starving . make sure float/needle and seat all work freely. thanks; sonny

[Scrivet]

Did you correctly set the governor connecting rod (to carb) linkage when you put the carb back on? Is there play between the governor rockshaft and the governor spring throttle? Both common and easily fixable.

Simple fixes first , cleaning the carb is good most people "throw a kit at it" when a good cleaning is all it needs. Same with the governor. Lots of stuff to try before you rip it apart.

Fuel flow easy check, take the drain out of the bottom of the carb and open the shutoff. Should be a steady stream about the size of the inside of the fuel line. Let it run into a clean container (so you can dump it back in the tank) for a good minute or more. If it's good there fuel flow isn't likely your problem, No or reduced flow work your way back to the tank.

[DanielV2]

Well, the simple fix wins again. I pulled the plug out of the carb and after the initial surge of gas, it slowed to barley a trickle. Took the fuel hose off the carb and still, only a trickle. Took the fuel line off and blew it out, put it back on and still just a trickle. Then I drained the gas tank and tried to unscrew the sediment filter assembly without taking the hood off. I was unsuccessful. So I took off the hood and got to the sediment assembly. Some trash had accumulated in the gas inlet. I cleaned it out with some carb cleaner and put everything back together. Now it is running with minimal surging. Thanks for everyone's help!

Daniel V

[randallc]

Did you set the governor with the carb after taking the carb off? Should not be "minimal" surging. Still need some adjustment.