A strange thing has started to happen on my 84 300D. Normally coolant temperature will run 90-95C stop-n-go, highway, etc. Occasionally when pulling a long hill at highway speeds temps will get to 100C or maybe a needle width past. If I fill the coolant to the "full" line which I assume is that little line about a 1/2" above the seam in the plastic coolant reservoir it will slowly puke it out the overflow line over a week or so until the coolant level stabilizes just below the seam in the tank. Thats the way it has always run and I just figure it to be idiosyncratic to the car. Heres the strange part: Well, now at the bottom of a highway offramp if entering into stop-n-go traffic the gauge will shoot up to 105-110C and stay there for a few minutes then return to 90-95C. Same thing happens if I hold the transmission in S to pull a long hill at 35-45mph. I flushed the system last year, new T-stat and cap. I am thinking either the radiator is clogged or the fan clutch is inoperative. Any ideas? RT

__________________
When all else fails, vote from the rooftops!
84' Mercedes Benz 300D Anthracite/black, 171K
03' Volkswagen Jetta TDI blue/black, 93K
93' Chevrolet C2500HD ExCab 6.5TD, Two-tone blue, 252K