C4 Corvette...1991 normal temperature question
09-05-2007, 02:25 PM
#1
8th Gear
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C4 Corvette...1991 normal temperature question
C4 Corvette...1991 normal temperature question.
'just have a question about my 1991 corvette. What is the normal operating temperature of this models?
I had the Thermostat and water pump recently replaced when my pump started making noise and now it's showing half to more than half of the gauge especially on the highway. Is this normal?
Is my vette starting to overheat after the water pump replacement?
Anyone has an input on this? Thanks in advance !
'just have a question about my 1991 corvette. What is the normal operating temperature of this models?
I had the Thermostat and water pump recently replaced when my pump started making noise and now it's showing half to more than half of the gauge especially on the highway. Is this normal?
Is my vette starting to overheat after the water pump replacement?
Anyone has an input on this? Thanks in advance !
. If you do a search on this subject you will find yourself knee deep in t-stat/temp related info. Have fun. 
09-05-2007, 02:38 PM
#3
Le Mans Master
There are many, many, many thread here that will tell you what the normal operating temps of these cars are. The search funtion is great and will save time.
On your model, both fans are controled by the ECM only. The primary fan come on around 228* and not too far past that the secondary fan comes on (235*). When the A/C is on, both fans run. You have two gauges on the dash that tell you the engine temp. The digital gauge (the more accurate) is displayed under the speedo. The analog gauge is to the right of the speedo. I rely on the digital gauge.
If the engine temps get past 240* start to worry.
On your model, both fans are controled by the ECM only. The primary fan come on around 228* and not too far past that the secondary fan comes on (235*). When the A/C is on, both fans run. You have two gauges on the dash that tell you the engine temp. The digital gauge (the more accurate) is displayed under the speedo. The analog gauge is to the right of the speedo. I rely on the digital gauge.
If the engine temps get past 240* start to worry.
Originally Posted by RRT vette
I spent about 45 minutes observing the coolant temperature operation range on my stock (never modified) 95 LT1 with 50,000 miles. I started the engine and let the temp rise. All of the info is while at idle and the outside temp 80*. Idle temp reached 228* before both fans came on and never saw the temp past 230* via digital guage. Analog guage was in the hash marks and showed approx. 250* from guessing, 260* being the highest number which is miss leading. The temp dropped to 217* and both fans cut off. With the A/C on the temps sat around 201-205* and never got lower or higher. This I consider normal at idle and when driving at about 55 mph the digital temp guage stays around 185-190* range.
09-05-2007, 03:04 PM
#4
Tech Contributor
Actually there is no digital temp gauge on a 91. (unless you want to count the outside temp gauge on the electronic climate control system) That option came out I beleive in 93. So he only has a analog gage next to the oil temp analog gauge. Yes I agree 240 is a cause for concern anything after 260 turns on the check gauges light and kills the AC. Anything below 240 is considered normal. Goldcylon
09-05-2007, 03:20 PM
#5
Actually there is no digital temp gauge on a 91. (unless you want to count the outside temp gauge on the electronic climate control system) That option came out I beleive in 93. So he only has a analog gage next to the oil temp analog gauge. Yes I agree 240 is a cause for concern anything after 260 turns on the check gauges light and kills the AC. Anything below 240 is considered normal. Goldcylon
09-05-2007, 03:49 PM
#6
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I have a '90, which is almost the same car. Operating temperatures in this car are higher than most individuals are accustom to, therefore I found it necessary to make adjustments especially living in Phoenix. 180* thermostat, you must also regularly clean between the radiator and the condenser. Also clean the radiator and condenser, do this by using a garden hose direct the spray from the engine to the front (reverse of air flow), do not spray on an angle as this may bend the blades / fins on the radiator. Also flush the radiator and get all the gunk / deposits from inside the radiator out. When replacing coolant only use the identical color coolant, if it is green use green, if red use red, do not mix or you will get not good jello. This is a closed system therefore most people do not know you must burp the system if you replace a hose, water pump, etc., as air becomes trapped within the closed system and overheating occurs.
Both fans come on when the A/C is turned on, when the A/C is off the fans will come on 235* -238*. If your car becomes heat soaked it will continue to climb over the 240* mark, this is the area which makes me quite nervous, as I have blown two (2) head gaskets due to excessive heat, one was due to a fan failure.
Do as suggested and use the search feature on the forum (advanced is better) enjoy the reading and controversy covering overheating comments by C-4 owners.
Hope this helps..................
Both fans come on when the A/C is turned on, when the A/C is off the fans will come on 235* -238*. If your car becomes heat soaked it will continue to climb over the 240* mark, this is the area which makes me quite nervous, as I have blown two (2) head gaskets due to excessive heat, one was due to a fan failure.
Do as suggested and use the search feature on the forum (advanced is better) enjoy the reading and controversy covering overheating comments by C-4 owners.
Hope this helps..................
09-05-2007, 03:58 PM
#7
Le Mans Master
For some reason I was thinking LT1 car. Thanks for the correction.
09-05-2007, 09:35 PM
#8
Tech Contributor
I have a '90, which is almost the same car. Operating temperatures in this car are higher than most individuals are accustom to, therefore I found it necessary to make adjustments especially living in Phoenix. 180* thermostat, you must also regularly clean between the radiator and the condenser. Also clean the radiator and condenser, do this by using a garden hose direct the spray from the engine to the front (reverse of air flow), do not spray on an angle as this may bend the blades / fins on the radiator. Also flush the radiator and get all the gunk / deposits from inside the radiator out. When replacing coolant only use the identical color coolant, if it is green use green, if red use red, do not mix or you will get not good jello. This is a closed system therefore most people do not know you must burp the system if you replace a hose, water pump, etc., as air becomes trapped within the closed system and overheating occurs.
Both fans come on when the A/C is turned on, when the A/C is off the fans will come on 235* -238*. If your car becomes heat soaked it will continue to climb over the 240* mark, this is the area which makes me quite nervous, as I have blown two (2) head gaskets due to excessive heat, one was due to a fan failure.
Do as suggested and use the search feature on the forum (advanced is better) enjoy the reading and controversy covering overheating comments by C-4 owners.
Hope this helps..................
Both fans come on when the A/C is turned on, when the A/C is off the fans will come on 235* -238*. If your car becomes heat soaked it will continue to climb over the 240* mark, this is the area which makes me quite nervous, as I have blown two (2) head gaskets due to excessive heat, one was due to a fan failure.
Do as suggested and use the search feature on the forum (advanced is better) enjoy the reading and controversy covering overheating comments by C-4 owners.
Hope this helps..................
Good input from another Arizona driver. If your not sure about the burping procedure just drill a couple of holes in the thermostat and the car will burp itelf. Goldcylon
09-06-2007, 08:38 AM
#9
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08-17-2017, 03:52 PM
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08-17-2017, 05:02 PM
#12
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C4 Corvette...1991 normal temperature question.
'just have a question about my 1991 corvette. What is the normal operating temperature of this models?
I had the Thermostat and water pump recently replaced when my pump started making noise and now it's showing half to more than half of the gauge especially on the highway. Is this normal?
Is my vette starting to overheat after the water pump replacement?
Anyone has an input on this? Thanks in advance !
'just have a question about my 1991 corvette. What is the normal operating temperature of this models?
I had the Thermostat and water pump recently replaced when my pump started making noise and now it's showing half to more than half of the gauge especially on the highway. Is this normal?
Is my vette starting to overheat after the water pump replacement?
Anyone has an input on this? Thanks in advance !
Infrared thermometer showed passenger side radiator hose temp to be less than 100 degrees when coolant temp was 210+ with fans on.
Last edited by car addict; 08-17-2017 at 07:20 PM.
