Hello, Engine runs fine, I have a starting problem. Crank the engine at different throttle settings with choke on and off engine does not start. New fuel, cranks good, but seems to lack fuel. If I spray starting fluid, engine starts immediately . I pulled the gas hose from carb and cranked engine. The fuel pump, pumps gas and appears fine. I'm not familiar with this particular carb. It has two wires connected to the bottom of fuel bowl, black is ground and gray, I assume is a signal. I'm thinking this may be causing the problem. Is this a fuel shut off or monitoring device. The engine starts fine with starting fluid, so it doesn't appear what is at the bottom of fuel bowl is the problem. Does not start cold or after running and I try to re-start. Engine has 121 hours on it and this just start happening in the last month. Any ideas. Thanks John

If it starts with a prime and continues to run, the solenoid at the bottom of the carburetor is not your problem. You may want to check the choke linkages and see if the choke is closing when the engine is choked.

I did check the choke linkages with an inspection miror and the choke opens and closes properly. This situation also happens when the motor is hot. Is there specs on the pump such as psi at cranking speed and/or running speed; or volume / min to check out the pump. It does pump gas at cranking speed but now I wonder if it is enough. Also, what does the solenoid do on the carb. Other than starting, I have no complaints as to performance. Thanks John

Service manual shows that fuel pump delivers 1.5 psi.

The solenoid is an anti after fire valve, it cuts the fuel supply off when the ignition key is turned off to stop the fuel flow into the engine through the carburetor jet. Sometimes fuel will collect in a hot muffler when an engine is shut off and you will get a large bang, this helps to eliminate the bang.

You may want to check the valve lash on both of they cylinders, valves way out of adjustment could make an engine hard to start.

I will check the valves out tomorrow. I found some wiring diagrams. I'm thinking now that the switch could be at fault. If the solenoid does not receive battery voltage at start position the fuel is block and won't start. By using starting fluid it starts on the fluid and when the switch is in the run position it receives the voltage and fuel. I could have a bad switch. I will also check this out tomorrow. Thanks John

That is entirely possible and something I have actually run across in the past, but something I rarely think of when troubleshooting this type of issue.

Good luck and let us know what you find... :thumbsup:

Problem solved. Found low voltage 6.7 volts at the solenoid. Cleaned the contacts on the starter key switch and now have 12 volts at the solenoid. The voltage was not enough to activate the solenoid when the starter was engage, but after starting with the fluid it must had received enough in the run position. Problem was caused by trying to keep the machine clean, I believe hosing it off after mowing caused the corrosion at the switch. Thanks again for your help, I was not familiar with that solenoid . John