Proper Highway Operating Temperature for 1977 C3
Brian
5.) Parked car running readings as follows : 200 on factory guage 6.) Upper Hose : 190 degrees 6.) Lower Hose : 173 degrees ... This seems in proper operating range for around town (? ) Highway may be a different story ...
Question : Is the Top Radiator Hose the more accurate measurement and are these readings accurate to the guage reading ? Meaning the top hose 190 # and the factory guage reading : 200 Degrees ? Also, as recommended : I adjusted the Emissivity Meter reading to 0.94 for hard rubber ... Important Note : These adjustments for different compounds make a Big Difference in readings ... up to 10 Degrees or so.
Any Further Input is Always Highly Appreciated !
Peace ~ Dee[/QUOTE]
Those readings with the car parked look normal to me, it tells us that the rad is doing it's job.
The best spot to read the warmest water temp is right at the thermostat housing....or the first couple of inches of the rad hose.
If your IR is reading 190 and the gauge reads 200 it's likely keeping the engine right where it should be with a 195* thermostat, do you know what thermostat is in there?
The engine does have to work harder at highway speeds, and therefore makes more heat. If you don't have the proper baffles and air dams in place the extra airflow from highway speeds might be going around the rad instead of through it....air will follow the path of least resistance....ALWAYS!!
Do you have the lower air dam or something similar to the one in post #13? If not you need to get one.
Hope this helps
1.) Missing anti-collapse spring in the lower (suction) radiator hose;
2.) No lower air dam to direct airflow up and into radiator; you MUST have one;
3.) Defective thermostat...not strong enough to keep flap open when W/P flow increases;
4.) Your radiator is caked with calcium carbonate on the inside of the cooling fins and is greatly diminished in its ability to cool. Look down into the radiator tank and check for a lot of brownish deposits on the walls/tubes. If you see this, you need to use radiator CLEANER (not 'flush') to get rid of that calcium build-up in the radiator. Find radiator cleaner in auto stores near radiator flush products. FOLLOW DIRECTIONS ON THE CONTAINER. This may be a bit of trouble...but it's lots better than replacing the radiator.
Last edited by 7T1vette; Sep 6, 2017 at 01:15 PM.













