Radiator cap on 1999 2.2 cavalier ?

SOURCE: 2004 Aveo Unknown will not start

Daughters 2004 Aveo stopped dead on freeway. Plastic thermostat on engine and melted off. Chevy said it blew the engine, searched on line and found 17 pages of same complaint. Chevy repaired car for free. Still not worth the worry. But if this is your problem, fight it don't pay for repairs!

SOURCE: Car running hot, clicking noise in dash when turn the heater on

Thermostate goes bad (it might be placed it reverse way) or gatting stuck not opening. Engine might die it you wont have it checked ASAP. Also if you bought an aftermarket cap (not for GM) it might cause the ptoblem with coolant pressure. Check that it says for how much psi.
Hope that helps
Good Luck

SOURCE: Help with cooling system!!

OK, firstly The basis that a cars cooling system runs on is very simple. The system is a pressurized cycle that moves the coolant around, along with the heat, and is slowest in the radiator to allow heat to escape. If the system is not pressurized then the cycle will not work properly and coolant will not move.
If there is air in the system this can create what would seem like a blockage. 'bleeding the system is not the answer especially if you are using the drain on the radiator. That drain is only for draining fluid not air.
If air blockage is the problem then what you do is open the system at the highest point possible. this is usually a hose at the top of the radiator or something, whatever is easiest. Then find the other hose attached to the radiator, lower, higher makes no difference. then simply squeeze the second hose. this will 'burp' the air out do this for a while until all that happens is fliud is pushed out repeatedly.
then reattach the top hose and top up the radiator, and go for a drive.
If this doesn't fix the problem then air is not the problem.

Radio Code Pro

• 2200 Answers
• Posted on Sep 15, 2009

SOURCE: how to drain 2001 chevy caviler radiator

Hi

It sounds very much from your description that there is a strong possibility of air being trapped within the cooling system and causing the problem. This will cause the low fluid warning to appear on the car and although the vehicle will appear to be full of fluid - in fact you cannot replace enough fluid because of an air trap in the system.

Most vehicles cooling systems can be bled by removing the cap from the radiator or header tank and then simply allowing the vehicle to tick over for 10 minutes or so. Check and replace the fluid as the air is expelled from the system through the open header tank/radiator.

This may well resolve the problem without any further action on your part.

Some vehicles do have specific bleeding procedures for the cooling system but as far as I am aware this simple procedure is the standard method with your vehicle.

Also it is important to pay attention as to why the vehicle is loosing coolant in the first place. Is there a leak any where - check coolant hoses are not cracked. Is vehicle overheating because of fan failure hence boiling off fluid? Is there evidence of water getting into oil pointing to head gasket problems?

These things should all be considered in addition to clogged radiator.

Hope this helps. Please do rate this answer. Thanks.

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SOURCE: I own a 1990 Chevy Lumina car. I had a new

The water in the overflow reservoir never boils. For water to boil, it requires a constant heat source, since boiling uses up heat energy so rapidly.

That appearance of boiling is from steam (or some other vapor) from the pressure side of the radiator cap being released into the reservoir, and that is not normal.

If the thermostat is installed backward, it will not open until the car is already overheated. The side with the copper button must be on the engine side. Heating that copper button is what opens the thermostat. If that button is on the radiator side, the water on the engine side must get hot, then transfer that heat into the cold water inside the radiator hose through contact with the closed thermostat. That would take 20 or 30 minutes...

Plus, as the water overheats in the engine, it starts to turn to steam, which does not cool very well, and does not transfer heat to the thermostat very well.

Once the thermostat does open, it allows cold water to suddenly cool some pretty hot cylinders. This can lead to cracking metal parts, and dramatically uneven cooling, setting up stress in metal parts and in gaskets between them.

Now, it is possible that water in part of the system was turning to steam before the water in the radiator got hot enough to operate the fan switch. You should make sure that the fan operates properly, but this sounds like more like improper cooling to me. Even with the radiator surface completely covered with something that prevented cooling air flow (a cardboard sheet or whatever), it would surprise me to see an overheat condition in under 20 minutes running the engine without a load (not in gear, in other words).

Now, one other thing. The proper operation of the thermostat when making the transition from a cold engine & radiator to a warmed up engine and warmed up radiator requires a properly functioning heater system. While the thermostat is closed, the water pump must be able to circulate water through the engine. It does this through the heater system.

Water from behind the thermostat leaves the engine through the heater hose by the thermostat, flows through the heater core, and is then routed to the water pump inlet. This water flows out of the water pump and through the engine, picking up heat (which cools the hot parts that heat came from) which it delivers to the back of the thermostat. If the heater core is clogged, or any part of the heater hoses has failed on the inside, such as delaminating, then having that delaminated part act like a dam), the thermostat will not receive the heated water from the engine promptly enough to prevent overheating.

From stone cold, when you start the engine, in 1 to 2 minutes, you should start to feel warmth when you grip the heater hose coming out from near the thermostat. As this hose starts to get too hot to comfortable handle, the upper radiator hose should start to warm up, slowly at first, then more rapidly. At first, the engine will get really chilly water from the radiator as the thermostat starts to open, closing it right away. As the water coming from the radiator starts to be less cold, the thermostat will spend much less time fully closed, and the radiator hose will warm more rapidly.

120ºF is the temperature at which you will not be able to leave your hand on a heated surface. The heat takes some time to travel from inside the heater hose through the heater hose material to the outside. So when the outside is 120º, the inside is quite a bit hotter.

If you are getting vapor pushed into the reservoir before the upper radiator hose is too hot to handle — and really, before the bottom hose is rootin-tootin hot — then the engine is overheating before making full utilization of the radiator.

One final thing: If you have a head gasket leak, that will directly inject exhaust gas into the cooling system. That does 2 things. 1) the vapor is hot! It is exhaust gas, after all. This introduces a lot of heat into the cooling system, rather than shoving that heat out the exhaust pipe. 2) that vapor will collect at the high points, such as under the radiator cap, and will build up pressure in the cooling system — the exhaust gas from the cylinders is high pressure gas. That pressure can force the radiator cap to vent long before the engine has overheated, causing the appearance of boiling in the reservoir.

There is a simple test for exhaust in the cooling system. A vacuum syringe — looks like a turkey baster — partially filled with a teltale chemical is used to draw vapor out of the radiator through the filler neck of the radiator. That which is drawn out bubbles up through the tell-tale chemical. If the chemical changes color, you have a head gasket leak, or a cracked combustion chamber.