Is there black smoke all of a sudden or why else do you believe that it is flooding? From your description on how you seem to get it up and running, maybe the fuel system isn't venting. Try loosening the fuel cap and see if you have the same result.

I agree - I can not confirm flooding but the fuel filter is filled to about 1/2 or 3/4 level - removing the line and sending air and the gas back to the tank helps - the process restarts - I will check the venting of the cap.
by the way, it is a B&S engine - 21HP model 441677-0113-E1
I will try loosening the cap when it stops raining!

***"the fuel filter is filled to about 1/2 or 3/4 level - removing the line and sending air and the gas back to the tank helps"***
PAY NO ATTENTION to a fuel filter that appears to be less than full. It means nothing. What does mean something is how you describe the sending air and gas back to the tank. If you actually SEE, the gas racing back toward the tank when you loosen the fuel hose........that is PROOF that the fuel tank was holding a vacuum caused by a non-venting cap (probably a clogged vent hole in the cap). Use a stiff piece of wire or paper clip to probe the hole in the fuel cap, both sides if possible. If you have compressed air, blow the hole out after probing.

makes perfect sense - there is a vacuum build up - I will cleanup the cap -
by the way, no black smoke!

I have a LA 135 and the same thing happened. It was a small seed blocking the vent hole of the gas cap.

the blocked hole in the gas cap was it!
thank you all for the help

Two thumbs up!

Make sure that the vent on the fuel cap is not plugged. Also, check the fuel line that is coming out of the tank. It is possible that the line is getting pinched between the tank and the frame causing lack of fuel flow.

Where is the charging port for the L120?

To check the charging system on an L120, locate the voltage regulator that is attached to the engine. There will be two yellow wires and one red wire on it. Unplug the stator from the regulator and use a digital voltmeter and check the AC voltage coming out of the stator-should be approx. 30 volts AC. If not, the stator is probably bad. The regulator has probably failed letting battery voltage back into the stator causing it to short out.

You guys rock! I have a plow blade on my Scotts 2048 and same thing...engine quit after 20 min and won't run for more that 2 sec on each start. I read this post, cleaned out the fuel cap vent hole, and I'm back in action.

Thanks!

Never had that problem,but am glad to know about it,so will check my fuel cap and hope I don't forget it in the future. This board has a lot of smart people on it,which makes me glads I found it.

My JD LA120A will run while pouring gas into carb. but when it runs out it will not keep running? I have loosened the cap, new fuel pump, plugs, inline filter? At the end and do not know where else to go?

ronharri - with the help of an assistant, try the following - remove carb air cleaner so that you can see into carb intake throat.
Using a rattlecan of carb cleaner (NOT ether), spray several shots directly into carb throat WHILE assistant is sitting in tractor seat and trying to start the engine in a normal fashion (cl/brake pedal fully depressed, PTO sw off, throttle @ 50%, no choke).
If engine pops and tries to start, you have a fuel delivery problem. If engine does not try to start, you have an elect/ign or mechanical problem.
Run test and report results back. We can then better advise you on next troubleshooting procedures. Good luck.

I just finished spraying cleaner into the carb and turning it over. The thing started and I mowed some already. II will try again tomorrow and if it works you all are my Hero's. Thanks!!!!