'63 skylark 215 overheating

[jstump63]

Is there anyone that knows of any things that are easily overlooked with these motors. I have replaced the radiator, water pump, thermostat, and I even tried burping the system. I'm not sure how long you take to burp the system though. As far as I know, the intake manifold gaskets were replaced by the previous owner. Some people have said the gaskets could be blocking a water hole in the manifold possibly. Is there anyone that could verify this. The coolant barely flows with the engine running at 200 degrees. It should be flowing vigorously correct? I have a 160 hi flow thermostat in it now. It runs a 200-210 going at speeds 55 and above. If i get stuck in traffic for too long though, it slowly creeps up to 240-250 degrees. Thanks in advance, any input is appreciated. I'm at a loss with this.

[d2_willys]

Is there anyone that knows of any things that are easily overlooked with these motors. I have replaced the radiator, water pump, thermostat, and I even tried burping the system. I'm not sure how long you take to burp the system though. As far as I know, the intake manifold gaskets were replaced by the previous owner. Some people have said the gaskets could be blocking a water hole in the manifold possibly. Is there anyone that could verify this. The coolant barely flows with the engine running at 200 degrees. It should be flowing vigorously correct? I have a 160 hi flow thermostat in it now. It runs a 200-210 going at speeds 55 and above. If i get stuck in traffic for too long though, it slowly creeps up to 240-250 degrees. Thanks in advance, any input is appreciated. I'm at a loss with this.

Sounds like the thermostat is not opening at all. I would check this first using a pot of water on the stove. Should open way before boiling water.

[jstump63]

I've had three different thermostats in it: A stock 160, hi flow 180 and a hi flow 160 which is currently in it now. All of them were new.

[d2_willys]

I've had three different thermostats in it: A stock 160, hi flow 180 and a hi flow 160 which is currently in it now. All of them were new.

Since you say that there is little flow, try warming engine up to where the thermostat should be open. Shut off engine and remove top radiator hose from radiator. Start engine and see if any coolant flows out the hose. Don't run the engine long like this.

Have you tried running without a thermostat to see if the flow is any better?

Another thing you might try is to drain the coolant out of a cold engine. Remove the top and bottom hoses from radiator. Take a garden hose and force water down top radiator hose (no thermostat) and watch how much water flows out bottom hose. If little or no flow, then there is some sort of blockage in the heads, manifold, or block.

[DeeVeeEight]

Is there anyone that knows of any things that are easily overlooked with these motors. I have replaced the radiator, water pump, thermostat, and I even tried burping the system. I'm not sure how long you take to burp the system though. As far as I know, the intake manifold gaskets were replaced by the previous owner. Some people have said the gaskets could be blocking a water hole in the manifold possibly. Is there anyone that could verify this. The coolant barely flows with the engine running at 200 degrees. It should be flowing vigorously correct? I have a 160 hi flow thermostat in it now. It runs a 200-210 going at speeds 55 and above. If i get stuck in traffic for too long though, it slowly creeps up to 240-250 degrees. Thanks in advance, any input is appreciated. I'm at a loss with this.

I am not familiar with the 63 but I did fight with my corvette for 2 years before licking the overheating problem.
First - is it a copper & brass radiator? Some of the newer ones are worthless, you might want to consider an aluminum radiator. Southwestspeed.com has some very reasonably priced aluminum radiators. I used a universal fit one in my 'Vette - it works GREAT!
Second - did you replace the radiator cap? They wear out, gasket and spring.
Third - is your fan shroud intact? It is important that the air be pulled THROUGH the rad and not be allowed to flow around it. Installing foam rubber pipe insulation (Home Depot, costs 2 or 3 bucks) between the shroud and the radiator will seal the gaps and improve air flow.
Fourth - is there a fan clutch and is it operating properly?
Fifth - is it possible that the return radiator hose is collapsing? They used to have springs inside the hose to keep them from collapsing. Most new hoses do not have the spring in them.
Sixth - a 160* thermostat is no good - it will not allow your engine to operate at the right temp range. Stick with the 180* stat. If you are worried about the stat get a RobertShaw fail safe stat - if they fail they open up instead of closing.
Seventh and last - Borrow an infra red laser temp gun or buy one at Harbor Freight (about $30) and CONFIRM that your temp gauge is accurate - point the gun at the heads when you suspect over heating and see what the temp gun says - Actually - I would do this FIRST as it will be a good and true indicator of what the temps really are. You can also point the IR temp gun at the radiator, T'stat housing and other areas to see what may be too hot or too cold.

Lee

[DeeVeeEight]

I just re-read your post for the 3rd time.... Have you ever flushed the cooling system out? It may be clogged with rust or other debris, that would account for the poor flow (even with a new water pump) and the over heating too....

[jstump63]

The radiator is copper and brass. I took the thermostat out altogether and replaced the radiator cap last night. It was 85 degrees in my area when I drove it last night. It ran between 210 and 220 at 55 mph. It got up to 230 degrees sitting in traffic. This morning I drove it to work and it didn't get up to 150 degrees, but it was only about 55 degrees. The flow of the coolant has drastically increased without the thermostat. I'm beginning to believe there is blockage in the heads or manifold. This winter I'm going to pull the heads and manifold and have them hot tanked and flushed out. One of the spark plug holes needs repaired anyways. There is no fan shroud or fan clutch. The car doesn't have ac. I have an electric fan mounted on it as of now. The radiator hoses aren't collapsing, I checked that last night. The IR thermometer is very handy. I've kept one in the glovebox for the past couple months now and the temperature gauge is accurate. Hopefully this setup will last 'til winter until I get time to pull the heads. I'm open to other suggestions though and thanks for all the input.

[DeeVeeEight]

Man, I feel for you. I really struggled with mine. It sounds like you have a pretty good handle on what you need to do. Good luck and keep us posted with your results, we can all learn from your experience.

Lee

[dynaflow]

The 215 was all aluminum, and it's possible previous owner(s) didn't use compatible coolant, which tended to clog radiator and cooling passages...your idea to clean passages sounds like a good one...