Until I recently replaced my radiator, my SDL would idle in city traffic at 100*C or so in the summer. I would turn off the AC when it went near 115*C. I've had the car since new and never let it get above 120*C. In over 20 years, I've not had any head problems. The owner's manual states that the temp will go up when going up a grade or in city traffic. Of course, YOU don't know if the car that you are looking at has been run with the temp in the red area which would be VERY bad. So, good luck. BY the way, you will love the car!

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Paul 1987 300 SDL; 2000 ML; '69 MGB; '68 VW Fastback