[oil pan 4]

First mod was a string. A baling string I found in my field plus a hole I drilled in the discharge flap that allows me to lift up the grass discharge flap to clear the cut grass so the blades to cut better, faster and put the flap down when the wind blows the grass and dust back at me.

I got a newer than 2010 craftsman riding mower as a pile of parts for next to nothing. A 46 inch single cylinder 19hp machine. I assembled the parts and it works.
Only lasting problem is the carb floods with gas, a bad O-ring allows gas to leak past the needle valve, I just need a carb rebuild kit so I can replace the offending O-ring.
Rebuild kit should be here today, so I'll see if it came in in the next day or 2.
If it still seems like it runs rich I'll get the "high altitude jet" that I found while searching for the rebuild kit.
It already gets much better fuel economy than my older 42 inch 18.5hp V-twin that drinks gas but the plugs last 2 or 3 years so I don't think it's running real rich.

The 19hp has plenty of power, it can easily shred the deck belt if I push it too hard, a $30 oopsie. So of course it totally makes sense to do mods that give it more power. I don't like smelling gasoline exhaust and pm2.5 soot is supposed to be really bad for you causing the side effects of one of those new medications. The ideal pipe for a 540cc 1cyl engine that spins 3,500rpm is a 1 inch ID pipe that is 5 feet long. Probably can't do 5 feet. But I could do a stack and get 3 to 4 feet of pipe on there. I have lots of 1 inch diameter, 0.062 inch wall 304 stainless steel pipe to use. So that works out good.

To use that power I will investigate the possibility of upgrading from a 1/2 to a 5/8 inch belt, it looks like a 5/8 will fit on the existing pulleys.

Bigger tires might be nice, the tallest deck setting is almost too low and 2 notches down out of 5 and the deck is on dragging on the ground. Taller tires would allow me to go faster not necessary but fun and should make a for a better ride over bumpy ground and cut the field grass higher.