Coolant Temperature
Thread Starter
Instructor
Joined: Feb 2017
Posts: 138
Likes: 6
From: Tallahassee Florida
Coolant Temperature
I have only had my 2001 C5 for about two months...and I have so much to learn about Corvettes in general and my car in particular. I had a pleasant drive through town this afternoon...more stop and go than I would have liked. It has been a warm day, but pleasant enough to have the windows down. I have gotten in the habit of having the coolant temp. selected on the screen. While idling at a stop light, the temp. reached 225 F... the red light changed, and off I went, and the temp. dropped. What is considered normal coolant temps. that should not raise concern? If something went wrong and the temp. got dangerously high, would I get a warning or what? And, when does the fan come on? A friend who has had a number of Corvettes says that running the defrost will keep those temps. lower...but that it really does not matter. Any info. would be appreciated. Barry
Racer
Joined: May 2014
Posts: 300
Likes: 34
From: Bella Vista, AR
When I'm cruising on the highway in 6th gear (manual trans) at 70 MPH, 1750 RPM, I typically see water coolant temps at 198 degrees and as high as 201 degrees. If traffic slows down and my speed decreases to around 60 MPH (still in 6th gear) temps rise to about 205. If I downshift to 5th gear and RPM increases to 2100 RPM temp decreases to about 196.
Stopped at a long red light, I'll see temps rise from 198 to around 205-208 degrees. A long line at a drive through on a hot day can send the temp north of 225 degrees and the fans will engage decreasing temps to around 210-214. Sometimes I'll turn the AC on to engage the fans earlier if it really starts to climb.
I'm running the stock radiator, original to the car (1999) and it should probably be retired soon. I'd like to put a Dewitt's all aluminum radiator in when I come to that point.
Stopped at a long red light, I'll see temps rise from 198 to around 205-208 degrees. A long line at a drive through on a hot day can send the temp north of 225 degrees and the fans will engage decreasing temps to around 210-214. Sometimes I'll turn the AC on to engage the fans earlier if it really starts to climb.
I'm running the stock radiator, original to the car (1999) and it should probably be retired soon. I'd like to put a Dewitt's all aluminum radiator in when I come to that point.
1/4 mile/AutoX
Joined: Jun 2014
Posts: 11,442
Likes: 2,186
From: Buffalo Texas
the LS engine in almost every other vehicle runs under 200 degrees, clean the radiator and condenser (back flush with water) I run a 180 stat and have a tune to run the fans earlier, runs 192 all day !!! THE WORST ENEMY OF A ENGINE IS HEAT !!!!
Le Mans Master
Joined: Oct 2012
Posts: 6,391
Likes: 1,453
From: South Dakota
On the road, my C6 generally runs between 201 and 205. In slow stop and go such as a parade, it has gotten up in the low 220's, but once you get moving, it will drop back down in the low 200's.
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Intermediate
Joined: Apr 2017
Posts: 44
Likes: 8
From: Western Ky
Thanks guys, I was looking for info on the coolant Temp. I bought my first corvette today and noticed how fast the temp risen during the test drive at a light, but then fell right away. It was in mid 80s, sunny and temp gauge went just past 220 at the light. I'm going to have it flushed just in case.
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IMO, your coolant temps are pretty normal in stop and go traffic. The C5 was designed to run hotter than cars you may be used to.
Drifting
Joined: Oct 2002
Posts: 1,773
Likes: 66
From: SoCal
When I'm cruising on the highway in 6th gear (manual trans) at 70 MPH, 1750 RPM, I typically see water coolant temps at 198 degrees and as high as 201 degrees. If traffic slows down and my speed decreases to around 60 MPH (still in 6th gear) temps rise to about 205. If I downshift to 5th gear and RPM increases to 2100 RPM temp decreases to about 196.
Stopped at a long red light, I'll see temps rise from 198 to around 205-208 degrees. A long line at a drive through on a hot day can send the temp north of 225 degrees and the fans will engage decreasing temps to around 210-214. Sometimes I'll turn the AC on to engage the fans earlier if it really starts to climb.
I'm running the stock radiator, original to the car (1999) and it should probably be retired soon. I'd like to put a Dewitt's all aluminum radiator in when I come to that point.
Stopped at a long red light, I'll see temps rise from 198 to around 205-208 degrees. A long line at a drive through on a hot day can send the temp north of 225 degrees and the fans will engage decreasing temps to around 210-214. Sometimes I'll turn the AC on to engage the fans earlier if it really starts to climb.
I'm running the stock radiator, original to the car (1999) and it should probably be retired soon. I'd like to put a Dewitt's all aluminum radiator in when I come to that point.
Thread Starter
Instructor
Joined: Feb 2017
Posts: 138
Likes: 6
From: Tallahassee Florida
Factory settings for the cooling fans coming on are as follows:
When the coolant temp reaches 226 degrees BOTH fans come on in low speed mode. When the coolant temp drops to 219 the fans are commanded OFF by the PCM. If the coolant temp reaches 235 degrees then BOTH fans come on in high speed mode. when the coolant temp drops to 226 degrees the fans revert to low speed mode. This is all if the AC is OFF.
With the AC ON then BOTH fans come on in low speed mode at 185 degrees of coolant temp. The fans remain in low speed mode until the coolant temp reaches 235 degrees when BOTH fans come on in high speed mode.
If the vehicle speed exceeds 35MPH the fans are commanded OFF ir-respective of coolant temp.
When the coolant temp reaches 226 degrees BOTH fans come on in low speed mode. When the coolant temp drops to 219 the fans are commanded OFF by the PCM. If the coolant temp reaches 235 degrees then BOTH fans come on in high speed mode. when the coolant temp drops to 226 degrees the fans revert to low speed mode. This is all if the AC is OFF.
With the AC ON then BOTH fans come on in low speed mode at 185 degrees of coolant temp. The fans remain in low speed mode until the coolant temp reaches 235 degrees when BOTH fans come on in high speed mode.
If the vehicle speed exceeds 35MPH the fans are commanded OFF ir-respective of coolant temp.
Safety Car
Joined: Mar 2015
Posts: 3,638
Likes: 245
I have only had my 2001 C5 for about two months...and I have so much to learn about Corvettes in general and my car in particular. I had a pleasant drive through town this afternoon...more stop and go than I would have liked. It has been a warm day, but pleasant enough to have the windows down. I have gotten in the habit of having the coolant temp. selected on the screen. While idling at a stop light, the temp. reached 225 F... the red light changed, and off I went, and the temp. dropped. What is considered normal coolant temps. that should not raise concern? If something went wrong and the temp. got dangerously high, would I get a warning or what? And, when does the fan come on? A friend who has had a number of Corvettes says that running the defrost will keep those temps. lower...but that it really does not matter. Any info. would be appreciated. Barry
