My 94 mazda 323 is boiling in the overflow tank. i have a ajustable thermate state that fix the promblem last time but now its doin it again. check by racq and they said that my fan is not kicking in.

manual adjustment ? then 12th inlet and 15th exhaust will suffice

THERMOSTAT STUCK CLOSE.

have it check because water tends to boil when it comes to the boiling point and it evaporates

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

It sounds as if the fan relay is sticking i would replace it and possibly coolant temp sensor as well, good preventive maintenance at lest, Hope this gives you a starting point ,if it is helpful please let us know, please feel free to ask again, Thank You.

your handbreak connects to the rear breaks follow the cable from your break drum where the 2 meet is the ajustment give it a squart of penertrating oil before ajusting as it has been open to the weather also there is further ajustment where the cable enters the hand break lever good luck ps if this dosent do the trick i suggest you cable is fully streched you will need to fit a new one

black smoke means it is over fueling try and get on top of the over heating problem first check you coolant level and may be remove the thermostat and check it in a bucket of boiling water if it dos not open replace it then you may have to reset your auto choke as this is yousaly the problem with over fueling on this model car

Relax, there is no problem.

When the water / coolant gets hot (inside of radiator/engine) it starts to boil, ofcourse when it boils, it expands, so the fluid in the radiator has to go somewhere, thats why there is the overflow reservoir. So, when the fluid boils, some moves to the reservoir to avoid any potential problems with the radiator, such as it blowing up, or not being able to cool off all of the fluid running through the engine.

But relax, its normal.

sound like timing problems. check timing belt or needs changing.

THERE IS TWO PORTS
ONE FOOR THE LOW SIDE , ONE FOR THE HIGH SIDE.
WHAT YEAR IS THE CAR ??
TNX