318 Overheating...Help!!

I wouldnt say 210 is "over"heating.....maybe running warm....but it depends on a bunch of factors...such as, is this the reading you getting sitting in sunny california traffic lol?

as was mentioned above....there is still many other possibilities that could be causing the problem.

do you have a worn out clutch fan? or do you have a stationary mounted fan that the blades have slightly bent outward over time? do you have a thermostat that is slightly sticking? ( I have seen junk "new" parts before also lol)....you can check by droping your t-stat is a pan of boiling water and check to see if it opens all the way.

do you have a radiator hose or heater hose collapsing? do you have a plugged heater core? bad intake gasket,head gasket? is your belt tight on your pullys? or does it have room to slip causing it not to spin your pump 100%?

tons of things to take into consideration.

if you want to save the cash on buying a new temp sender you can pick up at your local parts stores pretty cheap an infared thermometer ....good tool to have on the shelf for future work aswell.

just my .02