Thread: theorizing on rising engine temps

There really shouldn't be much evaporation, even if the system isn't getting up to pressure. Sure, the coolant will get hotter, but unless you are boiling the coolant, you shouldn't get much evaporation.

As others have said, I would start with the radiator cap. Cheap and easy. Then if that doesn't work, I would consider picking up an oversized radiator. They can be had for about $150. You can try to clean yours out, but I have heard that it doesn't work that well. But it is worth a try. Actually, being I am cheap, I would probably try that. I would rather put 8 hours of work into my car before I spend money on it.

But radiators do clog up from time to time, so this may be an issue.

Also, as for your temps, how hot are they getting? Right now, I am running a 195° stat, and my temps stay around 185° going down the road. In traffic, they can climb over 200° on a hot day. This change shows up a lot on the gauge, but when watching with my tuner, I realize it really isn't that hot, and so I don't worry about it. Anything less than 215° engine temps, I don't worry.