Sounds like old fuel in the carb. You probably need to diassemble it for a thorough cleaning and a new kit. Don't reuse the diaphragms.

Make sure that your impulse line from the base of the cylinder has not broken. The line runs from the cylinder to the elbow on top of the carb.

Thanks I will check this out.
Jim

assuming the fuel tank has some type of breather system, it may be blocked, does it runOK with tank lid removed?

I checked the vent hole and it seemed clear. It runs the same with the cap off.
Jim

I have the same problem, fuel lines in pieces. Replace lines as follows:

"The fitting on the top of the carb is for the impulse line from the motor crankcase. The fuel inlet is the fitting on the side of the carb where the linkages are. This carb has an external pulse to operate the carb pump.You should have another line from the fuel tank that is only a vent for the tank. It has a check valve inside the tank to alllow air into the tank as fuel is removed. If you have any more questions, e-mail me at palmede1@cox.net
Dennis"

Here is a link that might be useful: where I found it