I have 1 1993 Chevrolet s-10 4.3 v-6 model truck. It overheated one night. The gauge shot al he way up to red and then all of the sudden dropped back down to normal quick. The heatercore was aread going bad. So we replaced the heater cre. While replacing it we also saw the water pump was bad. So we replaced it too. Also replaced thermostat and all hoses. Well my son drove it for one week after that with no problems. Then all the sudden the gauge shoots up again. He also replaced the cap with a newer easier to open cap. We then replaced the temprature sensor. Also my husband can take the cap off with no boiling overwen truck is suppose to be all the way red, and also we have no heat when all the way red. We dont know ifyou have any ideas as to what itmay be. Our last three options were blown head gasket, clean and flush radiator, and the clutch on fan. Thanks for any ideas.
Are there any overheating issues, forget the lite/gage for a moment. Might be a problem with temp gage sending unit? You could use an infra-red temp gun, get engine up to operating temp, lite on, then check the temp reading with the gun. You can double-check the instrument cluster temp gage.
Might be some air in the system. I'd use the recommened lbs for the radiator cap.
December, 18, 2012 AT 9:34 PM
Okay I will tell my husband to see. He is actually doing an infared gun today. And get back to you
December, 18, 2012 AT 11:45 PM
Let us know.
December, 19, 2012 AT 3:06 AM
Hi wasn't sure what you meant by lbs on the radiator cap. More info on that please. Also we replace coolant temp sensor, is that the same as the temp gage sending unit. If not where is that located. He couldnt try the gun today it ran without getting hot. Thanks again ! : )
December, 19, 2012 AT 12:54 PM
I looked at the partsbook, the radiator cap spec was 16psi/pounds per square inch.
Your correct about the coolant temp sensor, signal for temp gage.