[C320-list] Temperature gauge

[Jim Pasley]

I have a 2000 C320, #691 with a Yanmar diesel engine. We took her out this weekend and I noticed that my temperature gauge is reading 240 degrees (max). I replaced the raw water pump last year and she is discharging plenty of water through the exhaust. Also, the alarm is not sounding like it did when the pump went out. Is it possible I have a defective gauge? If so, any suggestions for checking and or fixing it?