93 S10 Blazer
 

I can smell anti-freeze and today the temp gauge shot up toward 260 but the overflow tank is at the full line. I looked every where and could not find any signs of a leak or boil over. I have the 4.3 with 170,000 miles on it.

Any ideas?

Russ

check your pass. floor board and make sure the heater core isnt leaking

thermostat might be stuck closed, water pump might be dead, fan clutch or fan might be bad, cooling passages in engine could be clogged, if it 260 and didnt boil over maybe its a bad gauge