" I have cleaned the small hole in the gas cap. "

Are you sure it is actually open, have you tried removing the cap?

I am not recommending this to anyone else but if it were me, when the engine starts to die, I would place my lips against the gas tank filler neck and blow, do not inhale and reduce pressure before removing mouth from neck or gas will blow back on you.

Walt Conner

You could be looking a a fuel line that is old and collapsing. These also draw fuel through the top of the tank. Issue with the pick up tube? I'm unsure about what you mean about oil type air filter on this..

I had a LX178 several years ago.It would be mowing along and just die.After letting it sit awhile it would start and sometimes only run chocked.Was a very agrivating expierence.Because it did this when it was new and had me thinking it was a lemon.

The dealer would take it to his shop and it would run fine for them.Then they would bring it back and it would act up.One day it was acting up and the mechanic came out and removed and cleaned the carb in my garage.It was fine after that no more problems.He also told me to alway use high octane gas 91 or more not 87.So from that day forward I did and all was well.Not sure if the carb cleaning was the fix or the higher octane fuel?But never had anymore trouble in the 10 years I had that tractor.He said he had cleaned the carb the other times it had acted up.It would go awhile and act up again.So nothing more was done in my garage then had already been tried.But as soon as I started using high octane the problem was gone.

Have you switched gas recently from what you normally used?