Lawn mower help needed

[Mr.E]

Does this engine by any chance have the solenoid valve that screws into the bottom of the bowl jet stem? If so may be shutting fuel off (or slowing feed) as it heats up.

[Micky]

Thanks. At least I had reason to think that. Now I don't feel so stupid.

[83LowRider]

An uneducated guess? I've had a mowing business for almost 33 years.

1) I don't profess to be a mechanic. 2) I've never had a mower with a seat safety switch.

That said - can a safety switch not ground to chassis, or magneto and still receive a spark? As stated, not a mechanic.

What I DO know is this - I've used twin cylinder Onans, Kohlers, and for the last number of years, Kawasaki. NEVER have I had engine failure as a result of a bad plug OR a gas cap vent being plugged up. Maybe a push mower won't start as a result of debris between the electrode and the ground electrode... but that's about it. A spark plug will usually last for years. Also, 80-110 pounds of pressure is plenty. The OP would have seen other symptoms if he had a problem such as a bad valve, broken or worn rings. He mentioned no such foreshadowing problems. But hey, thanks for the smartass comment.

[trader_4]

Two problems with that theory.

1 - In his original post he says there is spark and every safety switch I've ever seen that stops the engine does it by cutting the ignition.

2 - In the newer post he has it running. It's clearly an issue of fuel starvation from the new symptoms.

[Diesel]

Silly question... But, is your fuel tank able to vent properly?

Try loosening the gas cap and see if it can start without the assistance of fluid. If it does, mess with the throttle. If it seems like it used to be, see if it'll roll with the deck running, as you'd expect. If it behaves normally, it's not properly venting and it's slowly being starved of fuel as a result when you force it to run with the help of a squirt or two. You can check the gas cap and try to fix it or just replace it.