Some S10’s have 2 fans. Mine has 2. Both are wired to come on at the same time. This truck is too old to know if this is the way it ‘should be’ or not.

You have to make dead certain that your cooling system has all of the air bled out of it or the water won’t flow properly, making it overheat.

The other point of failure is the water pump brushes have a short life. Pull the brush from the front of the water pump to see if it’s too short. If it’s too short, even with the spring, it will just not make good contact and cause your Dolphin to overheat.

Since your temp gauge went up so high, it means your truck got VERY hot. So you need to debug this issue to avoid damage. The temp gauge is not calibrated very well. It moves very little for a large temperature change.