TO35 Carburetor Rebuild, Good Idea?

My TO-30 runs great on level ground, but when I get on the hills with a load (tall grass and a 4' bushhog), it gets to surging and sputtering. I finally managed to get the field mowed by raising the bushhog up about a foot off the ground, closing the idle air completely and opening the power jet about 5-6 turns. It seems like it isn't getting enough gas under a load, but then when I get it set like that, it runs rough as h---, but at least it doesn't cut off going up the hills.

Last fall it was doing the same thing when I took it on hills, and I thought I might have some junk in the gas tank because when I unscrewed the fuel line where it goes into the carburetor, nothing would come out. I would blow in it, and then the fuel would come spurting out. Last week I took the sediment bowl assembly off, drained the gas tank and had a peek with a flashlight. The gas tank is in pretty good shape: not a lot of rust chunks floating around in there. There was some junk (pine needle) in the cylindrical screen which screws into the gas tank above the sediment bowl assembly, which I cleaned out, and it ran fine for one whole day (whoopee!).

Should I buy a new sediment bowl assembly, should I buy a new carburetor, should I rebuild the current carburetor? It�s a Marvel-Schebler TSX458. How hard is it to re-build? I took audio recording instead of shop in high school.

I went ahead with the rebuild using a kit purchased at Tractor Supply. The kit's diagram was no help so I cross referenced a diagram for the Marvel-Schebler for a John Deere M model. I wasn't able to replace the needle seat assembly, the one in the carburetor being far too snug for my tools. So the rebuild turned out to be a thorough cleaning with the added bonus of a new throttle shaft assembly. The jury is still out regarding the results. I had to stop work before finalizing the adjustments. The good news is I drove the tractor to the shed. Bottom line, what I did was not difficult; however, the fact that I did not replace the needle seat assembly may mean I could have better spent my time doing something else. The effort did not require specialized tools and I spent more time cleaning the carburetor than I did taking it apart and putting it back together. There is something to be said for a cleaning and a look inside the TSX, at least you'll know fouling isn't the problem source.

Jim

best wishes
TO