Troubleshooting Opel Astra H 2009 Z16XER: Water Boiling Post Head Gasket & Thermostat Replacement

Hello, I have a problem with my astra, I replaced the head gasket, piston rings, valve seals, thermostat. Now (I did not check before because the fluid was mixed with oil) after starting the engine, it boils water, the hose behind the thermostat is cold (as if the thermostat did not open) and a new one is installed (the entire housing together with the sensor), I will add that the head tightness has checked and it is ok so what could be the reason?

Well, check the thermostat and whether the plug holds pressure. Normal temperature in this engine is 100-103 degrees (light duty), the system cannot be opened.

But the thermostat is new, so how to check it? The water boiled with the plug unscrewed. I will also add that before I bought the thermostat, I made such an attempt that I took the thermostat completely out of the system and connected the fan to cool it all the time and then it was ok, the water was not boiling.

The thermostat for the water pot and see if it opens, as you say, the oil in the system, you know what's going on, maybe it clogged the radiator.

Only from what I read, the thermostat in this engine opens at 105 degrees, so I do not know if I will check it this way. I dismantled the old thermostat and there is a sensor there, like a heater and 2 tiny wires go to it, maybe it has something to do with this? maybe it opens it electronically? I don't know anymore, I will add that there is plain water in the system that can boil?

Screw the cap on and then check it, but without the temperature gauge in this car it's not easy ?.

maxiu99 wrote:

, I will add that ordinary water is poured in the system, can it boil?

hehe
I can afford the car, and 40 can not afford radiator fluid. ;)

Has gas by any chance?

Once, such a car had 2 hoses swapped at the rear of the engine, a similar effect.

Be , I only poured the water on trial to check if it mixes with the oil again, but the liquid is already flooded and the effect is unfortunately the same yes has gas.
The hose after the thermostat is cold as if the thermostat does not open and a new one is installed ...
And which snakes are these? those from the heater? or the smaller ones?

So you vented the reducer?

I thought you were still riding on the water Of course, the liquid / water at this temperature does not matter for boiling.

No, I did not bleed the reducer or the system because I thought it was bleeding itself, I did not see any vents there, will you tell me how to bleed it?

Well, you need to unscrew the cooling circuit at the reducer itself - where it is the highest. Forget that the venting system itself - it would vent if the reducer was much lower than it is usually mounted or in the absence of the reducer, of course.

Although I do not know if this will have an effect, the large circuit should run, i.e. the thermostat should open. But it doesn't hurt to check.

Do you have the reducer plugged in in series or in parallel? Because with a parallel one, the air in the reducer should not be affected - although in this case you would not be able to walk on gas.

You wrote yourself that the thermostat opens at 105 degrees, how not to boil water, in addition with the plug open. Pour the liquid, the liquid boils at about 130 degrees Celsius. And this heater is turned on by the engine controller when the engine is heavily loaded to ensure better cooling.

Water boils at 100o and when you say that the car works at 105o the answer comes by itself.

rs07 wrote:

And this heater is turned on by the engine controller at times of high engine load to ensure better cooling.

This is interesting.
Thermostat to check. The fact that new doesn't mean anything. Perhaps a muddy cooler. Besides, on short is to heat despite the closed thermostat.

2 serious mistakes:
1.Never, under any circumstances, pour water into the place of the appropriate coolant,
2. Never, under any circumstances, unscrew the cap when the engine is hot, or start the engine without the cap tightly closed.
Also read about phase thermostats.
https://autokult.pl/24875,termostaty-fazowe-po-co-komplikowac-proste-urzadzenie

FaNtOmAs1990 wrote:

Water boils at 100o

Only at a pressure of 1013 hPa. High in the mountains, it can boil at 80oC.

ociz wrote:

Only at a pressure of 1013 hPa.

ociz wrote:

Water boils at 100o

Only at a pressure of 1013 hPa. High in the mountains, it can boil at 80oC.

It is correct liquid water can be as high as 300 ° C under appropriate conditions and will not boil

I screwed on the new cap and I am still cooking, only the water pump and cooler to check ...

Has the problem been solved I have the same

In my case it turned out that there was a small hole in the hoses and the system was aerated and check the plug and whether the radiator in the left corner when you stand towards the car is hot because there is a fan sensor there.If you have no leaks and the hoses are hot then the radiator is fouled up or the thermostat.

Added after 9 [minutes]: .

You need to eliminate left air because a small leak like mine can boil water you need to first look for leaks check if the fan turns on in the radiator at the bottom corner is a sensor from the fan check with your hand if the radiator top and bottom is hot because if cold bottom is vented and the fan will not turn on check if the line from the thermostat and bud is hot and well vented heat up with 90 degrees and let the pressure out with the reservoir cap 2 times