Tc18 overheating

[rodster]

I have a tc18 from 1999 with about 750 hours on it. The last time I cut my grass, it started to overheat. Thinking it was the radiator screen and fins being clogged. Cleaned everything up, but that didn't fix the issue. Now when I start it, within 10 minutes or so, the temp starts to head up. I'm thinking it is either the thermostat or water pump. No fluid leakage. I was looking at a parts list, it looks like I need to take the water pump off to change the thermostat. Does anyone know if that is the case? I'm more of a shade tree mechanic where I would normally swap the thermostat first and then go for the water pump. But it looks like there is a couple hours of work to the job. Any thoughts are appreciated.
Rodster

 

[jinman]

I looked at the parts diagram and I think you are correct. It sure looks like the whole fan and water pump assy has to come off and be disassembled to get to the thermostat. It also looks like it would be quite easy for the coolant to bypass the engine if an internal water pump gasket is blown.