I have a 5 ft. Long finish mower,I was cleaning off the grass left on the top and placed my hand on the gear housing and thought hea that is warmer than I thought would be normal.So I used my lazer temp gauge the housing was 160 F after 3 hrs of running.So I checked the oil it was ok I check the spindle and belts they were all cooler than the housing.Would it be normal for the housing to run at 160 F ?