Question C6 Corvette - Overheating.

[Messner]

I have a Base 2007 Convertible with the paddle shift A6 on a 6 Liter.

Last fall when I parked her I noticed she was starting to run hotter, 230-235 etc.

When I pulled her out of hibernation yesterday (Calgary area) I removed the intake and the top plastic panel for the radiator to check for debris (perhaps the most common cause?). With a rag on a stick I removed at least a cup of dirt and sand from the front of the condenser! A bunch was blown out using a garden hose on the Rad & Condenser too. I think I’ll still change the thermostat as it may even be the original, I’m not sure.

After putting her back together I went for a drive. 50F ambient temps (cool Calgary April day).
The temps on the highway are at least 20 to 25F lower! It even gets down to the high 180’s at times.

In town and idling around in traffic it’s much cooler now, well under 210 most of the time and cools off more right after attaining 40Mph (and higher) getting more air into the system.

So if you’re having a overheating issue starting to occur, check this first the repair is free!!

PS My neighbour helped me to design a sprayer for the end of a garden hose that will fit between the radiator and condenser. It will help for behind the rad and fans too. I’ve yet to try it but know it will help clean these areas. Pics will be available if you need them - it’s a hollow metal tube. The end is blocked off and a small hole was drilled in the side near the bottom to spray sideways. This is attached to a garden hose and will make the job easier next time!

 

[XFIRE82]

Yup, that is one thing often overlooked when trying to solve a heating problem or a/c not blowing cold like it should. Keep the rads clean and it will make a big difference.

 

[RockyPM]

This is great! I’m buying a novi-stretch bra for the car and protect the rads. Our trip south we are going to need all the cooling available!

 

[Messner]

I have a Base 2007 Convertible with the paddle shift A6 on a 6 Liter.

Last fall when I parked her I noticed she was starting to run hotter, 230-235 etc.

When I pulled her out of hibernation yesterday (Calgary area) I removed the intake and the top plastic panel for the radiator to check for debris (perhaps the most common cause?). With a rag on a stick I removed at least a cup of dirt and sand from the front of the condenser! A bunch was blown out using a garden hose on the Rad & Condenser too. I think I’ll still change the thermostat as it may even be the original, I’m not sure.

After putting her back together I went for a drive. 50F ambient temps (cool Calgary April day).
The temps on the highway are at least 20 to 25F lower! It even gets down to the high 180’s at times.

In town and idling around in traffic it’s much cooler now, well under 210 most of the time and cools off more right after attaining 40Mph (and higher) getting more air into the system.

So if you’re having a overheating issue starting to occur, check this first the repair is free!!

PS My neighbour helped me to design a sprayer for the end of a garden hose that will fit between the radiator and condenser. It will help for behind the rad and fans too. I’ve yet to try it but know it will help clean these areas. Pics will be available if you need them - it’s a hollow metal tube. The end is blocked off and a small hole was drilled in the side near the bottom to spray sideways. This is attached to a garden hose and will make the job easier next time!

As summer continued my car was running warmer and warmer especially in heavy stop and go traffic on hot days. So I cleaned the rad/condenser again (made a bit of difference but not enough). I decided to go to the next step:

Excited & Getting ready for Kentucky!

Thought my (new to me last year) 2007 C6 Roadster might still be running a little bit warm. So best be sure she is ready for the trip which I’m sure will have some hot days and heavy slow traffic. (Can be hard on coolant temps).

Decided to start with the thermostat.
Went with a stock AC Delco - 86C (187F) thermostat (from Shaganappi Chev in Calgary) which was $100.00 cheaper than a local shops Cochrane (yes you read that right)!

First I checked it to make sure it was opening properly in a pot of boiling water and yes it was. Next I ran the car up on ramps and drained the radiator. Pulled the old thermostat out and replaced it with my new “made in Japan” AC Delco model.

Buttoned it all back up. Refilled her with Dex Cool and burped her several times to make sure no air was caught up inside.

Checked in with a friendly GM Mechanic who got me these stats for a 6 Liter, 2007 model:
1. Thermostat should start opening at 87C/187F.
2. Low fan should come on at 95C/203F.
3. High fan should come on at 113C/235F.
4. Warning lights on dash at 125C/257F (scary hot!).

It’s an easy job and I wouldn’t hesitate to do it myself again. Easier to get at (than I thought it would be) to get to what you need to. Car is running much cooler in heavy stop & go traffic now!

Saved just over $400.00 as that same shop wanted to flush it too and you guessed it - it did NOT need it! - Love my Vette!!!