I have a 1996 Chevy S10 Blazer 4x4 4.3
I am having trouble with it over heating. changed thermostat,not showing hot on gauge,no leak radiator,boils over few minutes after getting to destination, (20 min)drive,radiator or cracked block?
It sounds like you might have a clog somewhere. It is possible that the thermostat is not opening too. I know you said that it was just replaced, but it could be bad.
Thermostats are sold by temperature. If yours is not the right one for your vehicle it may not be opening at the proper temperature causing the vehicle to overheat.
If something is clogged it also will overheat because of bad circulation of the coolant. A cracked block would mean that you are losing coolant...are you having to add it? You will usually get thick white smoke out the tailpipe because the coolant is leaking into the engine and burning.
It also sounds like you may have a bad gauge as well. It should tell you when the engine is hot enough to overheat. Hope this helps.
〉 Answered on Jul 6th, 2009 by Lori Johnson, Owner and Instructor at Ladies Start Your Engines