Dang gone new fan clutch went out just as we climbed the last hill for home. Only 3k miles on it and the temp spiked to 220 and the clutch quit roaring I could hear when it went out. I hate changing that thing out. Good news is it the part is covered by warranty.
When it was working correctly, it would fully engage(roar) at 210 degrees(mechanical gauge) and bring the engine temp back down to 195 before reducing the degree of engagement. then it should slowly increase the degree of engagement as the engine temp rises to 210. (huge roar) If yours is not doing this it is defective.
I installed a 180 thermostat. It starts to open at 180 degrees and is fully open at 192 degrees. The OEM was a 195 unit and didn't full open until 210 degrees. I'd recommend changing out your stat with a 180 degree unit.
I found a huge crack in my SCS HVAC box when I changed out the fan clutch. Wouldn't have seen it if I hadn't been looking for it. this allowed hot air to enter the passenger side of the coach.
I also found that the when the fan clutch engages properly the ac works perfectly. When I turned on the factory electric aux fan it didn't help the cooling at all and it allowed the engine temp to go higher before full engaging the fan clutch. the only time the aux fan helped out was when I was at a standstill. So, when in doubt, suspect your fan clutch.
