504 International, No power under load

I have a 504 International that was running just fine, and for apparent reason just stopped running fine. It will start and run smooth as long as I have no load on it. However as soon as I engage the PTO to used the snow blower or manure spreader is chugs and pops and slows down and has no power to run anything. I can depress the clutch and it will catch up and run smooth until I let up on the clutch and then its right back to the chugging and popping. It also seems to have little to no response while under load when I give it more throttle. I’ve checked all the main things, carb, plugs, wires and distributor. All have been replaced in the last year (not the carb). Could this be an issue with the governor? If so what do I look for to know that it is? Any Ideas would be much appreciated.

Unrelated. On the bottom of the carb on the front side of the butterfly, there is what looks like a stone filter that screws right into the bottom? Is that what this is? Mine I can unscrew it and it is so plugged I can get no air thought it, I’ve soaked it in cleaners and still nothing. ( I say unrelated because it has been this way for years, but has always run fine)

Thanks

You are not getting enough gas to it. Take the sediment bowl off and make sure gas is pouring out of two holes, then work your was to the carb. Gas should run out of the drain hole in the carb, if the gas just kinda takes its on sweet time it is plugged.

Thanks will check that in the morning... Do you happen to know if there is a filter on the bottom of the intake side of the Carb that i need to fix?

There should be a screen in the gas intake line at the carb(unscrew the brass adapter the line screws into)