I recently purchased a 1988 560SL. When sitting in traffic, the temp gauge creeps up to nearly the hot mark (just under 120c). I've flushed the system, changed the thermostat & sender...any ideas? Is this normal? I noticed that the shop manual states that in traffic, the temp may go into the red. If this occurs, shift into neutral...that leads me to believe that it may be normal??
p.s. It doesn't appear to do it all the time.

 

it can't be normal because the operating temperature for 560 is 87 degrees centigrade.

fan clutch and auxilliary fan is okay? temperature sensor and teperature switch also need to look at.

last thing will be the leaky cylinder head gasket.

 

I checked the fan, it cycles on & off...the weird thing is, it's not consistent. Yesterday outside temp at 80F, it went up to 110c in traffic after about 10 minutes. Today, at 80f outside temp, I let it idle for 20 minutes and never went above 80c....