Hi Norm,
I'm sure you will sort it out. Somewhere I read that the Super 600 has a VEX 60 5hp motor on it. It should have a straight inlet manifold not the offset normal one. I'm not sure when the VEX 60 came out but perhaps after the orange PT 24. I would expect the shaft to be normal not long. No need for long as the pulley on mine was already too low. What do they do with the exhaust?. Newer ones seem to have a special slot for it. Whats the engine pulley look like? Is there a sliding plate or is the motor mounted straight on the base?
Noise could be anything but I am surprised that you have not heard it before. I guess the crank bearing has a different loading on it then normal with the belt tensioned up very tight as they must be. Mine does not sound the same as a normal PT. There is a slight noise from the belt and its noisier than a normal PT. I have had to put some extra packing in the muffler to quieten it down a bit. Sounds like a professional slasher which is what it is. Maybe ear muffs are needed.
All the best
Jeff
