yellowrose

My 72 Corvette will stay below 210 at highway speeds and idle, but when I stop and turn the engine off, the coolant goes to 220-230. I know because when I turn it back on after only a few minutes being turned off, the temp gauge reads that, and after that, it won't go back down. I also noticed when I turned it off at 200 deg, I have a lot of backflow into the reservoir and dumped 14+ oz of coolant on the ground. Any ideas/help PLEASE.

467-Ratman

First thing, welcome to the Corvette Forum! You will find lots of very helpfull people that will be happy to give advice. On your car I am assuming that it is stock with a belt driven fan? I would check and replace your thermostat first, Mr. Gasket makes a high flow unit and also the Stewart/Robert Shaw stat is the best. You can buy them direct from the Stewart web site, they also make a very high quality water pump as well. Check your radiator cap and replace it, while your at it drain the coolent and put in fresh. Those are the two things I would check first, it seems that since you are running somewhat cool on the road its not airflow through the radiator, the fan clutch might not be working right either. Your water pump may be the culprit too. Good luck and keep us posted on the progress.

Robert N

Start at the radiator. Check for bent fins, damage and possibly have it check for flow problems. At lower speeds, it may lose its ability to cooler due to restrictions in flow. Also check the fan clutch and water pump. Thermostats have no bearing on lowering the temps.

I can run at 180 degrees whether at idle or speeds in 110 degree desert heatand I have a stock setup with no overflow bottle.

killain

Three things that all above have mentioned, 1. Make sure the radiator is working VERY WELL. This is really important, but more so in a corvette. Replace the thermostat and leave the cap off when you start it and make sure it is flowing coolant. 2. All though form seals around the radiator are important, make sure they are all there and sealing. Most likely you have a bad thermostat and or a clogged radiator. My corvette runs 200 around town and 210 out on the turnpike 3. Welcome.


[Modified by killain, 5:56 PM 9/27/2003]

GDaina

If the cooling fins have seperated, and it doesn't take many, the radiator looses it's ability to function. Normaly, the fins seperate on the bottom two rows. If that's the case, time for a new one, if you ave an aluminum rad. Copper....recore.