Did a very extensive search while trying to diagnose the problem so if anyone knows a thread this was already discussed in, please feel free to post it here. Engine is a CV23S-75590 that is brand new which served as a replacement for a 25hp Kohler that was on a Great Dane Chariot w/61 inch deck. It seems to run fine unless the blades are engaged then bogs down and blows a bit of black smoke out the muffler and blows a bit of gas out the carb when the pto is engaged. I checked the governor and carb to make sure they were properly adjusted and took the belt off the clutch, but the engine ran normally. Checked the plugs and they were really sooty. Whenever the control levers are firmly applied or when the mower is going uphill, I can feel the wheel motors/pumps squealing as if the engine doesn't have power. It didn't do this when I had the 25hp kohler but it did bog down at the end of its service life of 2660hrs which is why I had to replace it. I expected to get very similar power out of the 23 but this is not the case. These Chariots came with the 23 or 25hp option so I'm thinking either something is improperly adjusted or simply not working. Thanks in advance.