When you let the engine warm up until the fan comes on, do both the upper and lower radiator hoses feel pretty close to the same temperature?
I already changed thermostat part. look diagnostic acquired.
A- i started the engine in cool, the gauge is completly down. 0 time.
B- the gauge move to 1/4 at 2 minutes.
C- the gauge move to 1/2 at 10 minutes.
D- the gauge move to up almost red line at 18 minutes.
E- the fan start running at 24:00 minutes.
G- the fan stop running at 24:52 minutes. the gauge came down 1/8.
H- temperature increase to D again at 26:10 minutes.
I- cicles repeated since D, almost the same with diference times.
Do you have an "point and shoot" thermometer so you can check the engine temperature at various locations? If not, a regular thermometer submerged in the radiator fill hole will verify the coolant temp.
No sorry, i did not find anyone. i did: run engine 30 minutes and stop, living engine get cool a few, by 2 minutes, open radiator (no problem to open cap, no pressure, no gas, just a few liquid spended) and introduce a normal thermometer, it show 120° F, the maximus at thermometer is 150° F.
i did not try it again seen to be dangerous in case of the cristal blow up.