Tends to use water. no obvious leaks, replaced radiator and thermostat valve

A hot running engine is usually caused by a cooling system problem. Make sure the coolant level is full and the thermostat.. rad fan.. radiator cap and water pump are all functioning correctly. Make sure there are no restrictions in front of the radiator to obstruct air flow and coolant circulates properly throughout the radiator. As for losing oil, check for the obvious..... Leaks. If no major leaks and you have a high mileage engine, suspect the oil to be burning within the engine. A constantly hot running engine can also cause the oil to break down quicker resulting in consumption, especially if oil changes are neglected

could be head gasket leaking if there are no obvious leaks from hoses,gaskets,radiator etc

its obviously thermostat

most of the cars made for Europe are equipped with a( thermostat ) but don`t confuse it with air conditioner thermostat or thing is working like valve that stops water circulating in cold starts so the water will only circulate around the engine block not through the radiator and of coarse it helps heat up your car`s engine faster but the problem comes when that valve got old (by the way most of those valves working as a wax capsule when the water heats to some amount the wax molten so it opens the way for water to circulate through the radiator ) what happens is simply the wax looses some of its function and molten in higher temp . so it block the water again until it heats up to molt the wax my advice : get off that part and just don`t replace it if you found it pricey for you your car still working but will needs more time to warm up i hope i was useful for u sir .
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http://auto.howstuffworks.com/cooling-system2.htm

If you plugged the original leak (which sounds like the head gasket) and then the radiator was leaking, and you are having water coming out of the exhaust, then you need to replace the head gaskets. It sounds like you had a blown head gasket from the start. Here's what to do.

1. Replace the head gaskets (will need intake manifold gasket as it need to come off for this procedure).

2. Replace thermostat, radiator cap (if radiator is still good)

3. Replace water pump; the water pump may have stopped working (mechanical), which in turn caused the pressure to build an blow the head gasket (the cause of the pump would be a bad thermostat. If the truck was overheating, then the thermostat was bad to begin with, then the pump, then the head gasket, so then the only place left for the water to go is out the exhaust.

Here is a list of replacements:

^ water pump
^ thermostat
^ head gaskets
^ valve cover gaskets
^ radiator cap (if radiator is good)
^ radiator : if leak from cap caused any damage to radiator (should still be good)

**Also check the radiator hoses to ensure they do not have any "bubbles". Hot water over time (with anti-freeze) erodes the inside of the hoses, and begins to "dig" holes and grooves in the hose, which evetually cause leaks. Consider replacing these as well for safe measure.

Please, let me know if you need further assistance.

carsandcomps,

Guru, Premium Expert @ Fixya.com

If there isn't water obviously appearing from somewhere it's either a head gasket failure or radiator cap. Check the oil filler cap for emulsion. Just hope that it's the radiator cap.

Toyota Celica, Corolla, ECHO & MR2 1999-05Toyota Celica, Corolla, ECHO & MR2 1999-05

2002 Toyota Celica 1.8L MFI DOHC 4cyl

The thermostat is located in the water inlet housing that is connected to the lower radiator hose.
The thermostat is equipped with a by-pass valve. If the engine tends to overheat, removal of the thermostat would cause a decrease in cooling system efficiency.

CAUTION NEVER drain coolant directly onto the ground! NEVER open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. Also, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.


Fig. The oil filter must be removed to access the thermostat on the 5S-FE engine

1. Position a suitable drain pan under the radiator drain **** and drain the cooling system.
2. On the 7A-FE engine disconnect the engine coolant temperature switch harness from the water inlet housing.

Fig. Disconnect the engine coolant temperature switch wiring located on the side of the thermostat housing

1. Remove the oil filter on 5S-FE engines.
2. Loosen the hose clamp and disconnect the lower radiator hose from the water inlet housing.

Fig. Loosen the radiator hose clamp ...



Fig. ... then slide the hose off the thermostat housing

1. Remove the two nuts from the water inlet housing and remove the housing from the water pump studs.

Fig. Only two nuts hold the housing to the cylinder head



Fig. Pull the housing straight out to remove

1. Remove the thermostat and rubber O-ring gasket from the water inlet housing.

Fig. Then pull the thermostat and gasket out



Fig. Sometimes the gasket is stuck and has to be pried out of the head
To install:

1. Make sure all the gasket surfaces are clean. Clean the inside of the inlet housing and the radiator hose connection with a rag.
2. Install the new rubber O-ring gasket onto the thermostat. On 5S-FE engines, align the jiggle valve with the upper side of the stud bolt. Insert the thermostat into the housing.

Fig. Only use the correct temperature range thermostat when for replacement



Fig. Align the jiggle valve within a 10°gap of the stud bolt-7A-FE engine



Fig. Align the jiggle valve within a 5°gap of the stud bolt-5S-FE engine

1. Position the water inlet housing with the thermostat over the studs on the water pump and install the two nuts. Tighten the two nuts to 78-82 inch lbs. (9-10 Nm).

Don't forget to install a new O-ring onto the water inlet pipe. Apply soapy water to the O-ring prior to installation.

1. Connect the lower radiator hose to the inlet housing and install the hose clamp.
2. Attach the water temperature switch connector.
3. Install the oil filter and check the oil level if removed.
4. Fill the cooling system with a good brand of ethylene glycol based coolant.
5. Start the engine and inspect for leaks.

1. Remove the right hand cover under the engine.
2. Drain the engine coolant.
3. Remove the fan and generator V belt.
4. Remove the generator assembly
5. Remove the water inlet via the two nuts.
6. Remove the thermostat.

To install:

1. Install a new gasket onto the thermostat.
2. Install the thermostat with the jiggle valve upward. It can be set within 10 degrees on either side of the prescribed position.
3. Install the water inlet via the two nuts. Torque to 8 ft. lbs. (11 Nm).
4. Install the generator assembly.
5. Add engine coolant.
6. Inspect for leaks.
7. Replace the cover under the engine.

I hope help you with this (remember rated this help) Good luck.

Locate the thermostat. The thermostat is in a metal housing at the end of the radiator hose where it connects to the engine.

Drain enough coolant to make the water level below the the thermostat level so that the coolant doesn't spill everywhere...

Remove the thermostat:
The housing is held down by two bolts.
Remove the bolts, remove the thermostat and scrape the gasket and sealant from the housing and the manifold.

When replacing, use Permatex #2 - non-hardening gasket sealant.

Replenish the radiator with 50/50 coolant/water mixture (re-use what you took out; don't pour down drain or on grass - kills vegetation).

Remove radiator cap and let engine warm up (look for leaks) to allow trapped air in the cooling system to escape.
Note: there may be some burping valves near the thermostat. If obvious, open them to allow air to escape.

Hope this helps!

Yes it looks like it. Provided you installed the thermostat in the correct direction, Here's the test, remove the radiator cap, start the car and wait for the engine to warm up, When you can see the temp begin to rise on the gauge the thermostat will open. While reving the engine look for turbulance in the coolant/antifreeze in the radiator opening.
If none is observed then replace the water pump.

sounds like one of 2 things, the thermostat or the engine has a leaking head gasket, replace the T-stat 1st, if the problem persists have the engine tested for blown head gasket(s) if the radiator was the problem u would have circulation and engine would overheat very slowly or just hotter than normal.

Are you losing water from the radiator or expansion tank and need to keep topping up? Did the fault occur before the radiator & thermostat were replaced or only since?