Hot Water Heater Replacement
If it is not leaking, I would check out the thermostat first. I recently replaced my thermostat with one from Home Depot-$8. It literally took less than 10 minutes. You can also replace the heating element almost as easily. It should not be a problem to replace the water heater yourself either. There are only 5 connections. 1/2 fresh water input/hot water output, 3/4 heat exchanger engine water input/output, and 5 electric power. Keep in mind that before you disconnect the fresh water you should turn off the water pressure or wear foulweather gear. Also realize that engine coolant water goes thru the heat exchanger so coolant will drain out. It would be best to catch the coolant so you can put back in after the replacement is connected. Most important - turn off and disconnect power first! Hope this helps.