1990 overheating in traffic reserve tank boils over

Could be a defective radiator cap, or a leaking head gasket.

Hi there the common problem found with your car is one thermostat sizes and will not let the water pass threw this in turn will cause boiling in the head and overflow bottle .2nd have a look at water hoses around engine and radiator they leak a bit , if no leaks are found my guess thermostat

you have a blown head gasket.. doesn't have to have coolant in the oil for a blown head gasket... if hoses are rock hard when running then you have exhaust leaking into the coolant via a blown head gasket...

where do you put the coolant show me a pioctures

Answer could be a faulty thermostat,or it could be a sign that your head gasket is about to blow ,or last of all your timing could be out of sync.

Answer 2 from Inventus: It means your cooling system is funtioning properly. In a system having a coolant recovery tank, coolant in the radiator is always up to the brim, hot or cold. There is negligible or no air space. When coolant in the radiator expands sufficiently due to warming from the engine, it will squeeze past the pressure cap's bottom seal and flow into the recovery tank. (If no provision for such expansion was present, the expansion would rupture the radiator or your hoses.) Only coolant within the radiator is under pressure, and because of this pressure (together with the elevated boiling point that the "anti-freeze" permits), it normally does not boil. But once past the pressure cap's bottom seal, the overflow is at atmospheric pressure and therefore boils.
This boiling is usually unnoticed after a short, i.e., local, trip because the cooler coolant already in the recovery tank quenches it. But after some highway driving the influx of more hot overflow heats up all the coolant in the recovery tank to the (unpressurized, i.e., "natural") boiling point.
As the engine cools when shut off, the contracting coolant in the radiator sucks back coolant from the recovery tank. Fluid in the recovery tank should never be below the "full hot" or "full cold" marks, lest air be sucked in.
-- BETTER ANSWER ==
Your cooling fans are not turning on. It is not normal for your overflow tank to boil like that. It is true that your radiator is overflowing into the reserve tank, but that means yourr adiaotor is boiling. Check for blown fuses or relays for your cooling fans. IF theya re fine. run your engine for about 15 minutes and drive. When you temp level is at normal operating temp open your hood with the engine runing and see if your fans are on. If they are, then you may have a bad thermostat or a plugged radiator, or a bad water pump. If the fans are not on, get your cooling fan switch replaced if your car has one. Check your temp sending sensor

Warm up the car and pay attention to the coolant reserve tank.
If you see bubbles raising up from the bottom of the reserve tank then you has exhaust leak at the head gasket,
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The shop method is a coolant system pressure test and hydrocarbon dye test.

Due to the complexity of the newer cars on the raod today!! what you are experiencing is Normal!!! since the coolant systems on the newer cars run at such a higher pressure and a high Rpm the reserve tank which has it's on drain hose for excessive overflow from the radiator allows the extra high pressure release from the radiator to back flow to the reserve tank and then out the reserve tank overflow hose on to the raod

replace radiator cap system depends on good pressure to keep from overheating

Try a new radiator cap.

Ford 2000 Taurus

To solve the problem you have the things to do in this order;

) When the engine is cold top off the radiator with fluid. (When the pump was replaced the fluid should have been also)
) Make sure the radiator fluid has anti-freeze in it. This is also anti boil also !
) Add fluid to the overflow reservoir.
) Make sure the drive belt was replaced on the water pump.
) With the engine running, you can add fluid to the radiator for the first minute or so. You want to get air pockets out.
) Replace radiator cap.
) Let car warm up. When it's hot you should get the radiator fan coming on.
) When it get hotter the air-conditioning fan may come on.
) If the fan does not come on, the heat sensor is probably bad.
) If all fans come on, and it overheats, you may have a bad thermostat. Trace the upper radiator hose to where it connects to the engine. That's where it located.

Do not operate the engine when it overheats, You will damage the head gaskets and cause radiator fluid to leak into the cylinders.
If you smell radiator fluid in the exhaust fumes, it may already be leaking.