When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hey there. Need some advice from those of you in the know. I had my '77 completely restored and am having some temp. issues. Here's the rundown:
Idling, the temp gauge shows about 210 or so.. Running down the highway with the A/C on, she hits in the red (about 250-260). I have replaced the sending unit with an AC Delco one (had duralast), but still shows the same. Radiator is new, flow is good. Water pump is new, Thermostat is new (put another new one on in case the other was bad).
BUT..... Infrared thermometer on the thermostat housing unit while "allegedly" so hot shows about 210 or so. The car exhibits no sign of being hot after shutting it off (pinging, boiling over, etc.). To me, it sounds like my gauge (they are the original gauges). Is it possible for the gauge to be off 40-50 degrees??? It appears to operate fine with it dropping back all the way down after cooldown.
Any advice would be greatly appreciated!!!!!!!!!!!!!!!
Buy a new sender from one of the Corvette-only suppliers like Eckler's, Rik's, or Corvette Central. Your present sender is surely not calibrated for your gauge as your infrared heat gun is indicating a lot cooler temperature.
I have one, it is accurate and is measuring the water temp directly. A non contact thermometer can vary due to emissivity. A more accurate temp with one might be found on the hose just after the thermostat housing, if you are using black rubber hose.
I have one, it is accurate and is measuring the water temp directly. A non contact thermometer can vary due to emissivity. A more accurate temp with one might be found on the hose just after the thermostat housing, if you are using black rubber hose.
Those "radiator cap thermometers" are worthless because they measure the temperature of the coolant AFTER it has been cooled. Just another worthless gimmick to put your hard-earned dollars into someone else's pocket.
Those "radiator cap thermometers" are worthless because they measure the temperature of the coolant AFTER it has been cooled. Just another worthless gimmick to put your hard-earned dollars into someone else's pocket.
Interesting. Is that why it agrees with the gauge inside my car?
Sitting at idle with the hood up is the only way to read it right? The temp it senses is in the radiator...true. Has that water been cooled? Not in any significant way, until my electric fans kick on.
Even then the fans cool the water, the inside temp thermometer reflects that and so does the one on the radiator cap.
Then the fan cycles off and the temp begins to rise agian. Shown by both the inside temp gauge and the radiator cap thermometer
.
Should it be your only source of info regarding water temp? Of course not. No more than a non contact thermometer that is subject to emissivity variations and errors should be.
Far from worthless.
Took a drive in the '77 vette to town today to drop off the wife's car for alignment. when I got home I popped the hood and snapped a picture of the cap temp and then a pic of the temp indicator inside the car. Both indicate 180*. This is immediately after pulling into the garage and the cooling fans had just shut off. Looks like the cap temp gauge is pretty accurate.
1977 Temp Issue
