Welcome to the Corvette Forums at the Corvette Action Center!

Water Temp Rises 225 during Idle/Traffic

D

Dr C5 Corvette

Guest
Hi, I have noticed my temp Gauge rising to 225-230 during Idle and traffic without the air on. need some suggestions, no codes at this time. How important is the gm coolant . I have topped off with Prestone 50/50 mix a couple of times in the last several months . There is no Order of coolant, could the Stat be going Bad or the cap on the Tank leaking ?............ Thanks Dr C5 Corvette ;help

Ps: I dont here the fans come on with the temp rise only if I have the air on
 

Hotwing

Well-known member
Joined
Feb 6, 2006
Messages
249
Location
Pasadena, Maryland USA
Corvette
2004 Torch Red Coupe
Mine is the same and I think thats kinda normal in traffic. Check your manual as I think they dictate a certain kind of coolant .....I cant remember off hand ;)
 

bradfordsvettes

Well-known member
Joined
Mar 28, 2001
Messages
549
Location
Boston, MA area
Corvette
jewel blue 61.cranberry 69 t-top.black rose 92
that is the aprox temp that the fans turn on all computer controlled steve
 

redvett

Well-known member
Joined
Dec 16, 2001
Messages
486
Location
AZ
Corvette
2001 Convertible
The stock PCM is set to run the secondary fan at 237F. Nothing is wrong and as long as it toggles between 195F and around 237F your fine . You may want to check & clean the space between the A/C condenser & radiator for leaves & other trash.
 

zagger

Well-known member
Joined
Apr 22, 2006
Messages
468
Location
San Diego
Corvette
99 C5 Convertible
Redvett is absolutly wright:upthumbs .

As for the coolent only Dexcool should be used.:nono If you add other type of coolent there can be an a reaction cousing the existing Dex. to jell and plug up the whole system. There has been a lot of threds about the subject, just search this forum.
Good luck.
Zig.
 

gmjunkie

Well-known member
Joined
Nov 11, 2004
Messages
4,547
Location
Old Fort NC/Vero Beach FL
Corvette
03 Z-51,78 L82 Coupe
The stock PCM is set to run the secondary fan at 237F. Nothing is wrong and as long as it toggles between 195F and around 237F your fine . You may want to check & clean the space between the A/C condenser & radiator for leaves & other trash.
My fans Kick on at 228 if I'm not running the A/C it will creep up tp 232 before comeing back down!!!!:upthumbs
 
D

Dr C5 Corvette

Guest
Ok I will Look Into that. Maybe I should drain ,flush and fill with new dexcool. where is the drain for the cooling system? Thanks dr C5 Corvette
 
D

Dr C5 Corvette

Guest
Ok Thanks, that made me feel a lot better Thanks Dr C5 Corvette
 
D

Dr C5 Corvette

Guest
Ok Drained out most of the old dex cool and refilled with Prestones New GM Approved DEx Cool at a 70% Mix with Distilled Water. Now no more temp rise and stays aroung 197 even in Hot weather and traffic with the air on. I guess the dex cool was diluted to much from previous owner I am HAPPY!!!!! Dr C5 Corvette
 
F

fdxpilot

Guest
If you have your AC on, the fans will run any time you are under 30 MPH and the coolant temp is over 165. If you turn off your AC, the fans will go off and your temps will rise just like you noted in your first post. At about 228 F (approximately, the temp varies slightly with model year), the fans (both of them) will come on at low speed. At about 235 F, the fans will go to high speed. The temps you mentioned in your post are ops normal for an unmodified C5 cooling system.
 

redvett

Well-known member
Joined
Dec 16, 2001
Messages
486
Location
AZ
Corvette
2001 Convertible
Using a mixture of more water than AF will increase the heat transfer not decrease it. I keep my Corvettes at -15 F and never have heating problems as long as the radiator is clear of debris in front of the condenser and between the condenser & rad.
 

zagger

Well-known member
Joined
Apr 22, 2006
Messages
468
Location
San Diego
Corvette
99 C5 Convertible
Using a mixture of more water than AF will increase the heat transfer not decrease it. I keep my Corvettes at -15 F and never have heating problems as long as the radiator is clear of debris in front of the condenser and between the condenser & rad.

Please correct me if I'm wrong, but the modern coolant fluids when mixed in proper ratio with water change the molecular makeup of the fluid. It makes it denser and therefore able to absorb more heat, which makes it more efficient in cooling. The boiling point of water is 212 F. with coolant it is much higher.
 

TODD L GRIFFITH

Well-known member
Joined
Jul 12, 2001
Messages
1,120
Location
Middleboro, MA
Corvette
99' MR Coupe, 04' Silverado 03' ZO6 Sold
There are a few things you can do to drop the temp. For me I have high compression 12.5:1 so I use the 160 degree thermostat and bring the fans on at 180 degrees. This gives me alittle extra protection against detonation. On a hot day I run between 175-185 degrees. Another thing I did was removed the plastic shroud in front of the radiator as well to allow room for my bottom fed Vararam. The extra flow from underneath keeps it cool all summer long. One thing you can do is add the ZO6 grilles in the fog lamp locations. The Gen III's are happy around 190+ anyway. I think the flush did you alot of good. Glycols tend to loose their efficiency after awhile.
 

redvett

Well-known member
Joined
Dec 16, 2001
Messages
486
Location
AZ
Corvette
2001 Convertible
Please correct me if I'm wrong, but the modern coolant fluids when mixed in proper ratio with water change the molecular makeup of the fluid. It makes it denser and therefore able to absorb more heat, which makes it more efficient in cooling. The boiling point of water is 212 F. with coolant it is much higher.

Water is a much better heat exchanger than a mix of water & AF. The only reason that AF is used is to lubricate,corrosion preventive, and raising the boiling point & freeze protection.
I belong to the ZR-1 Net and we had a engineer at the NCM from GM that explained it all to us way back in 1994 before the LS engines were around.
 

TODD L GRIFFITH

Well-known member
Joined
Jul 12, 2001
Messages
1,120
Location
Middleboro, MA
Corvette
99' MR Coupe, 04' Silverado 03' ZO6 Sold
Water is a much better heat exchanger than a mix of water & AF. The only reason that AF is used is to lubricate,corrosion preventive, and raising the boiling point & freeze protection.
I belong to the ZR-1 Net and we had a engineer at the NCM from GM that explained it all to us way back in 1994 before the LS engines were around.
I agree 100% this is absolutely correct. I work with alot of different levels of glycol mixtures for anti-freeze protection for building chilled and hot water systems.
 

zagger

Well-known member
Joined
Apr 22, 2006
Messages
468
Location
San Diego
Corvette
99 C5 Convertible
I stand corected, eaven that I'm not 100% convinced. Freazin, lubrication and heat trasfer are three differant things and car cooling system has to combine all three to make a best possible combination. The nice thing about this board is the amount of knowelage all of us bring to the table. I had a simular problem with heat and my solution was to replace the radiator with a aftermarket thicker core one. This was after the old one developed small crack in the plastic tank. Without changing thermostat or reprograming the fans the car stays in the 190 to 205 range. It all depends on how I drive the car. Before the temp would range from 190 to 235, a much higher temp differance than now. Living in So.Cal. freazung is not an issue, so I'll try changing my ratio of water/Dex. and see if it makes any differance. :w
 

Don Forster

New member
Joined
Feb 12, 2007
Messages
4
Location
Upland, Ca.
Corvette
2000 magnetic red
water temp rise 225 idle/traffic

This post caught my eye, as I have the same problem with a 2000 C-5. I'm curious if a switch or other method could be used to activate the fans and keep things cooler. Would that cause any obvious problems that I see? It really bugs me to see the temps in the higher readings when the fans could keep everything more normal. Any comments would be helpful...
 
F

fdxpilot

Guest
It really bugs me to see the temps in the higher readings when the fans could keep everything more normal. Any comments would be helpful...

Depends on what you mean by normal. Do you mean what used to be normal on old style, iron block SB chevy engines, from the 50s to 80s? Or what Chevy designed the system to do with the Gen III small block, with a bottom breathing, low drag sports car? Sure, you can run your fans all the time, and the temps will stay closer to 200 F. Just turn on your AC, and the current system will give you something close to that.
 

Corvette Forums

Not a member of the Corvette Action Center?  Join now!  It's free!

Help support the Corvette Action Center!

Supporting Vendors

Dealers:

MacMulkin Chevrolet - The Second Largest Corvette Dealer in the Country!

Parts/Accessories:

Vetteskins

Advertise with the Corvette Action Center!

Double Your Chances!

Partners

Top Bottom