engine temperature E300 Diesel

[cascais]

I just bought a 1995 e300 diesel with 200K and I have a question regarding engine temperature. The engine temperature is running between 90 and 100
regardless with or without the A/C on. It has not gone above it but the outside temperature is about 63%. Does anybody have an idea what are the specs for this model? if the outside temperature goes up to 85 to 95% summer temp whats next? i checked the thermostat,the radiator fluid and the fans and they are ok?

please help!!!!