Water boiling back in the resevoir after running 10 min thermostat is new and so are hoses. then car starts to run bad and shuts off.

I don't know how did you test your radiator but if you apply below steps you can clarify your problem easier.

If you want to test your radiator:
A) Park your car (it takes more longer to get real temperature values, if the car is moving)
B) Start the engine (don't forget to engage handbrake)
C) Wait around 10 to 15 minute
D) If your top radiator hose gets hot and bottom radiator hose gets warm; your radiator is functional. (In few minutes your radiator fan suppose to work)

If bottom radiator hose is still cold, it means there is a problem at thermostat. If you see any leakage at thermostat housing at the end of above step C, you need to renew thermostat housing gasket too. Even if you buy new thermostat, i suggest you to test it before assembly. If new thermostat doesn't open enough, your car may run so hot.

If you would like to test your thermostat:
A) Boil water in disposable bowl (thermostat may exposure chemical substances)
B) Put thermostat into boiling water.
C) If thermostat opens totaly, it is ready for assembly.

check that you put the thermostat in correctly. The body of the unit goes into the water in the head or block and not into the hose.

an faulty thermostat will make the car boil but the water will normally go to the resevoir bottle. I be checking for burst radiator hose or cracked top tank before anything else. Thermostats are c;osed when the engine is cold and as the water heats up they open and allow water to pass through the radiator to cool. Coolant over the engine means boiling and escaping through an opening (hose,tank punctured radiator etc)

Thermostat temperature senecer needs to be replaced

Remove thermostat and test it by dipping it in cold water ib an open pot. Heat the water on the stove while observing the thermostat. It shold opel just before the water boils. If it does check the radiator itself for clogging. Also fluch the engine water galleries.

Heres a couple of things you can check. Start your car and remove the radiator cap,(before it gets hot mind you) when it reaches norm operating temp, look inside radiator to see if water is circulating. If its not moving, its a bad water pump. Also, youre hoses should never collapse, if they collapse when they get hot maybe you need new hoses? Finally, if those dont work, flush out your radiator. Open the bottom cockpit and use a garden hose and let it flush out the system while the car is running, about 10 mins should do the trick. If the radiator looks clean inside then it doesnt need flushed.

Blown head gasket in between two of the cylinders do a compression test on all cylinders

follow the hose to the engine. Proably need metric tools proably 13 to 19 mm. undo the clamp. slide the hose off. undo the bolts. to ck thermostat put in pan and bring to boil to see if it opens. if not then scrap off gasket install new gasket also red perma gasket install the gasket and bolt it back up. put the hose back on and top of anti freeze. Start car and run for 20 mins to allow to get up to running temp and check for leaks

First if you coolant is boiling over you may have one on the following problem, bad thermostat-stuck closed. bad water pump bad radiator fan or fan switch or antifreeze leak-bad hose etc. Bad head gasket. Contact if you need more help,thanks for using FIX YA

Hi,
If the car is overheating it could be due to a thermostat which is stuck in the closed position, a failed water pump or just a slack belt driving it. I think there will be a "little" tube carrying coolant from the engine to the coolant expansion tank, and if you run the engine with the filler cap removed you should see water coming through that pipe IF the rump is running. A failed water pump will not necessarily leak, it just won't pump the water round the engine.

Always take care when dealing with a pressurised cooling system on an overheating engine - the water may well be above boiling point.

If you run the engine without coolant the cylinder head may well warp and repair bill will be huge.

Hope this helps you a bit. D