Engine Overheating?

Good chance head and/or gasket was damaged take compression test to determine.

Have you checked if you are getting power to the fan rather than running power to the fan? Also, the fan should kick around 205 degrees. The cooland sensor should be located near the thermostat housing. Also, it is normal for the cooling system to build pressure ane the hoses to get hard when the engine is hard. The fan relay should be in the power distribution box under the hood. And, if you follow the upper radiator hose to the engine, it will at the t-stat housing.

As far as a schematic, I will continue looking for that. Let me know if this helps.

Joe

First, thermostats do not cool engines down. They are designed to help the engine get hot to a certain point, then the water pump and radiator cools the engine.

The fist thing to check is the radiator cap/surge tank cap. Remove it and look to see if the black rubber gasket is intact and not clogged with dirt. Next start the engine and let it reach operating temp. (This is when the thermostat opens) There should be pressure in the hoses. If no pressure is building, then the radiator cap/surge tank cap is leaking.

Then you can check to see if the water pump is working by squeezing the upper radiator hose while someone revs the motor up and down. If you feel the pressure in the hose, then your pump is ok.

You can check your thermostat by feeling both the upper and lower radiator hose after the engine runs for about 10 minutes. (After the thermostat opens)

If the upper hose is hot and the lower isn't, then the thermostat is stuck closed.

Also, if you've added coolant after a loss, then you could have air in the system. You can bleed this air by removing the radiator cap and allowing the engine to heat and cool a couple times. (You need to set the heater on high) Also, with the radiator cap on but the surge tank cap off, squeeze the upper radiator hose a couple times while the engine is running.

Next, are you cooling fans coming on? At idle after the thermostat opens, the fans should come on. If not, check the relays. If the relays are good and the fans are getting power but not turning on, the the fans are bad.

Finally, if none of this works, either you have a blockage in the system, or a blown head/intake gasket.

You can easily check a blown gasket by first looking in the oil. If it's milky white, the gasket is blown. If not, open the surge tank cap and start the engine. While someone revs the motor, look inside the surge tank. If you see large bubbles (Not foamy bubbles), then you head gasket is blown and it's allowing hot exhaust gas to build up in the system.

Hey CHARLES,

These cars had a big problem with blown head gaskets which will make the engine overheat. Here are a couple of guides that will help you find out what the problem the is and how to fix it.

https://www.2carpros.com/articles/head-gasket-blown-test

and

https://www.2carpros.com/articles/engine-overheating-or-running-hot

Please run some tests and get back to us so we can continue helping you.

Best, Ken

With all they did, it shouldn't overheat unless there is another problem. Let me know, does it overheat only when sitting in traffic or does it do it when you are at highway speed?

At this point, my primary concern is a bad head gasket. Check the oil to make sure there is no coolant mixing with the oil. Also, check the coolant to make sure oil isn't mixing with it. Next (WITH THE ENGINE COLD) remove the radiator cap and start the engine. Let me know if coolant blows out.

Joe

You have a drain valve at the back of the motor, but there is no bleeder valve. The easiest way to bleed air pocket is to let the engine run with no radiator cap until normal engine temp. Just watch for coolant level coming out of the coolant cap neck. If coolant shots out, shut off the engine.

You cannot simply remove the thermostat. That will have ranging effect on all kinds of things, especially in the computer controls. Thermostats don't just suddenly cause overheating problems. You could have any number of things going on now since it has a history of overheating which could have done serious internal damage. Check all your fans for operation and pressure test the system for leaks. If it is overheating more at highway speeds, rather than idle, that would tend to point to a bad radiator.