My MEP803A (2012 Letterkenny Reset with 53 hrs) overheated and shut down during a 105% PF run a few weeks ago so I changed out the thermostat. I bought a new Onan Thermostat on the auction site with the correct NSN # (6685-01-360-9653) and part # (186-6193). It is rated at 74C (165F). All good until I notice the one I pulled out of the generator was rated at 88C (190F). I ran it yesterday for several hours and the Temp gauge never got over 175F at 105%PF. I ran at 113%PF for around 40 minutes until it tripped out on overload - still 175F temperature. I reset and continued to run at 105% to the end of the 3.5 hour run. The manual says normal run temp is between 170-200F. As I was idling down at end of run the temperature dipped to 160F. Ambient temperature during run was 42 - 49F. Have I created a problem with this 74C thermostat and if not does anyone know why Letterkenny installed an 88C Tstat? I'm wondering if I should attempt to find one rated at 80C. Thanks.
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