whiteyoda93

ok. I have a 93 22re. a few weeks ago my temp hand went about 3/4 across. never actually read hot. I shut it off and could hear the coolant boiling in the expansion tank beside the radiator. the next morning I drive it to town and temp hand never goes past 1/2. since then I have replaced the thermostat and radiator cap. haven't heard the boiling again but when I shut off the engine and look in the tank I see some air bubbles coming out of the overflow tube. truck only has about 14000 on rebuild. it's not using oil or coolant. no milkshake on the dipstick when I check oil. no steam out of the tail pipe. my question is. could I still have a blowed head gasket? since new thermostat the temp stays about 1/4-1/2. fan clutch is good also.

ksti

If you want to make sure, pressure test cooling system (also cap) and do a block check for exhaust gases in cooling system.