I agree with Diseasel. I live in the same area as Ismalley. Yes, we have had 122F days but now it has cooled down to 112F! I've owned a 190, 124, E420, Cl500 and now my last a '97CL600. The 190 has the least cooling capacity but I've never had mine peg. Sounds to me like it is hose, thermostat, radiator, and possibly water pump time. The E420 and the CL's barely get above 90 even with the AC on and at a 15 minute idle. Sounds like you need some work done.
Anziani
'97 Cl600 62K