Well, not really dangerously hot, just hotter than I think it should be. For some history, 8 years ago it was running about the same temp as it is noe. I took the radiator in to a local radiator shop, and he cleaned out, but did not rod it out. After that it ran as cool as I feel it should. Was good till last summer when I noticed it getting hotter than I normally like to see it. Last week I took the radiator out again and took it to a different shop because the old one had retired. He rode it out and told me it was pretty dirty. Figured that should do the trick. Put the 160 thermostat back in and drove it today. 90 degrees out, which is normal summer temp. in Nebraska. Runs the same temp on the gauge as before Roding out. It runs about 3/4 of the way up on the gauge. I know that isn't really hot, but is not normal for this car. Forst started to drive, the temp climbed to just about where I would figure 180 would be, and then obviously the therm opened and it dropped to where I always think 160 is. Then it sloooowly went up to what I figure is around 200 or better. I only drove about 15 miles. What should be my next course of action? Maybe try to flush the block with some vinegar??