How the carb is fed makes no difference. If the fuel level is higher than the float needle valve face the fuel can syphon.
FWIW most AYP mowers are buit to California legal specs and have solenoids fitted.
They are not a legal requirement down here but I see identical tractors in my shop, a USA grey import will nearly always have a solenoid.
The Australia import version, if there is one ( AYP excluded ) does not have a solenoid.
And perish the thought some times the marketing departments tell porkies to make imposed changes palatable to purchasers.
It also discourages the anti town hall red necks from ripping them off & chucking them away.
Even governments will find some positive spin to put on an onerious imposition.
If you don't want the mower to after fire all you need to do is to throttle down for a few seconds.
If the mower companies wanted to stop it all they had to do was add about 3" of exhaust pipe which is a lot lot lot lot cheaper than shoving a $ 50.00 airtight anti spark fuel explosion safe solenoid on the end of the float bowl.
However they could not do that because the muffler has to run hot enough to burn the fuel that the engine does not which was again the cheaper alternative to fitting a real afterburner which is called a catalytic converter another bald faced lie to make the $ 1000 box on your cars exhaust pallatable to Joe public.
Now if you really want to get it from the horses mouth, ring your local EPA and ask them if you are allowed to remove it.
So I have been told fines in the thousands for tampering with them in some states.
No idea about local regulations in Texas but I but a lot of engines from the USA shipped from Long Beach Ca and it is always a real PIA to get non -Cal compliant engines shipped to my consolodating agent in California prior to shipping.
